# Spray Bar Flow



## jameson_uk

So I have read the sticky about flow and lots of other info but I am not sure if I have an issue or not.

I have an Eheim 2217 filtering my Juwel Rio 180 with the dark grey installation kits.
I had the spray bar across the back pointing slightly up at the surface which I believe should create flow like:



 
The issue is that the spray bar only covers about a third of the tank so the flow is like


 
The tank looks like


 
This is low tech so no CO2 but the flow is pretty poor around the driftwood on the right hand side of the tank so not sure the plants here are getting the nutrients they need.   I get leaf little collecting in the top right hand corner.

I moved the spray bar to run across the left hand side and this caused a lot more flow and I could see the Vallisneria start moving (no swaying at all with the spray bar across the back) but I am not sure whether this will just move the problem to leaving poor flow around the swords???

What is the best setup in this situation?   Do I want all the plants swaying?  Do I need to have visible flow all around the tank?

I guess the ideal solution would actually be a second filter with a spray bar on the right hand side but that is not an option (currently) but I could get extra sections for the Eheim spray bar to increase the length (I just need to ensure the area of the holes is less than the area of the pipe?; and that is the 12mm pipe from the filter not the area of the spray bar tube???)


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## Chris Jackson

You could set it on the right side of the tank above the inflow so that you get a circular flow along the length of the tank. Lengthening the bar will drastically reduce the flow pressure so isnt to be recommended. 

It's nice to have visible movement in all areas but in low tech mode you shouldn't need to worry too much, gentle circulation will do the job.


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## Daveslaney

Could you not add a circulation pump between the end of the spray bar and the right side of the tank same level as the spraybar pointing forward at the front glass?This would get you the extra water movement in the right side of the tank.With the same flow pattern as your spraybar.


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## ian_m

If running low tech ie no CO2 gas or liquid carbon and lower light, flow rate is not so important, which is why most "complete tank kits" you buy, the filter flow rate is only 2-3x the tank volume. Many people run tanks for years with such a low flow rate, it is fine.

If you are having a "worry", you could either buy more spray bar (or make your own from acrylic pipe) to extend across the whole width or get a small power head to push the water around a bit. Generally probably not necessary if low tech, though.


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## jameson_uk

jameson_uk said:


> I am not sure if I have an issue or not.


So sounds like nothing to worry about.   Main concern was that there was basically no flow at the back behind the wood (flow would go to bottom front right corner and then into the intake in the back right hand corner).

I will leave as was as this might actually help; I am thinking about adding some Amazon Frogbit and I guess with the setup blowing across the tank this will just end up flowing round.

Thanks all


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## Jamie McGrath

why dont you just get extra bits of spray bar and fit it all the way across the back of the tank? I did this and found that the water was coming out of the holes too slow. I overcame this by putting a spot of super glue in ever other hole, the flow is now acceptable.


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## jameson_uk

I extended the spray bar so it now covers about 70% on the length of the tank and have it pushing out just onto the water line to create some surface agitation but obviously the has reduced the pressure so there is now very little visible movement below the water line. I think it is now very slow when it gets to the glass on the opposite side.

Just trying to figure out what the best setup is.
I know that I need surface agitation to make sure there is oxygen in the water but I know I don't want too much as this will get rid of the CO2 that the plants need (during the day anyway).
I also know that I need some flow to ensure the nutrients are being shipped round to all the plants but as this is low tech I guess all of this is not as important as if I was adding CO2.

I guess at some level the fact that the intake is sucking out water and it is being pushed back in by the spray bar means there is turnover and I also guess that the ideal turnover would be all the water in the tank and not just the same bit of water going through the filter and half of the tank being stagnant.

In a water system I would add some dye to see how it flowed but this is not ideal with fish and plants... Should I be looking for a little flow over the plants with their leaves gently swaying? If so would a flow pump be a good idea or would this likely cause too much flow as they seem to be designed for marine tanks and upset the fish and uproot plants? Perhaps an air pump with a couple of bars to generate surface agitation and making the spray bar point down into the water might help??

So question is how I do I know I have the right mix (or more importantly, how would I know if I have it wrong?)


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## jameson_uk

Anyone?    Took a video earlier of pressure coming out the spray bar.

Which if you look towards the end you can see that in the gap between the end of the spray bar and the inlet / edge of tank there is no surface movement at all.
I also took a video at the start of a PWC to show what is coming out


I feel this is not actually strong enough to reach the glass on the opposite side of the tank (surface movement does not look visible) and also there is no movement around that bit of driftwood near the inlet.

Should I be looking for more than this?   Presumably the surface agitation is enough for gas exchange but is this actually generating enough current to get everything into the filter and provide the plants with nutrients?


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## ian_m

Hmm seems awfully low flow. Generally the spray bar should be about 1cm below the surfaces.

This is my spray bar on my Vision 180 from a JBL1501 (1400l/hr) so not even the required x10 turn over for a high tech planted tank. I have the 600l/hr internal filter and a 3200l/hr power head as well.


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## jameson_uk

ian_m said:


> Hmm seems awfully low flow. Generally the spray bar should be about 1cm below the surfaces.


It is an awkward height because of the layout of the Rio and the Eheim spray bar.   Although it doesn't look like it in the video, the top of the spray bar is about at water level with the holes about 1cm underneath. (well the left hand side sits a little proud and slants down to the right hand side).   The original (shorter) spray bar was as per the pic a few posts up and about 7cm under the water but was generating flow.



> This is my spray bar on my Vision 180 from a JBL1501 (1400l/hr) so not even the required x10 turn over for a high tech planted tank. I have the 600l/hr internal filter and a 3200l/hr power head as well.


Somewhat different....
I am running low tech and the Eheim 2217 is suposedly rated at 1,000 l/hr) so on the 180l tank this should be about 5x turnover (which I believe is OK for low tech ???)
Think I will clean the filter over the weekend and see if it is gunked up (it has been running for a few months and I suspect there is a lot of plant crap that got in there).   I will then take the time to actually measure the flow rate without the spray bar attached to see what it actually is)

I am assuming that the actual movement in the tank is a problem then?   Would adding a flow pump or powerhead actually help (Assuming the filter is doing the required turnover than this would help the tank flow) but is this not really a fix at all?   Should I look to block up every other hole and see how this improves the flow rate?


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## Paul L

The holes in the spray bar on the Eheim installation set are larger than that of the regular green one. The water exits the spray bar more freely resulting in less water movement on the surface and in the main body of water. Extending the spray bar has compounded the problem quite a lot having seen your videos.Have you tried it with just three sections? It's easy to pack too much media in the Eheim classic canisters which could also slow the through flow. Is your filter tightly packed? As already suggested, a powerhead or wave maker would help with water movement. I recently installed a Tunze nano stream to my 55 gallon tank that has an Eheim 2071 and a 2075 running, and it's made a positive difference to the movement of water.


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## Andy Thurston

jameson_uk said:


> I am running low tech and the Eheim 2217 is suposedly rated at 1,000 l/hr)


I run that filter on my high tech 40x40x40cm with only 2 of the supplied blue sponges and custom stainless spraybar. I found the holes in the standard eheim spraybar too large to generate decent flow. The best way to generate better flow with this filter is to make the hoses as short as possible. My spraybar has 7 x 3mm holes in it. Based on this I would recommend trying a custom spraybar with 10-12 x 2.5 mm holes or 12-15 2mm holes, evenly spaced the full length of your tank.


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## Jamie McGrath

cover up every other hole with a bit of tape to see if this improves the flow, if it dose then cove the holes using something more permanent like glue.


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## jameson_uk

Wondering whether a second filter would be a worthwhile investment in the future ....

If I was to add a circulation pump would the output from the spray bar be generating enough surface agitation and the pump could generate the flow (a lot cheaper than a new filter) or should I really be looking to fix this flow at the spray bar?

For now I will clean the filter, measure flow and then try blocking up holes.

Same question as before though, how will I know I have adequate flow?  Should I be looking for obvious movement hitting the opposite glass and gentle swaying of all plants?


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## Paul L

My recommendation would be to ensure the canister filter isn't packed too tight, reduce hose length if possible, take off extention spray bar pieces leaving only three sections.

This is the circulation pump I've got no my 55 gallon tank , it's silent in operation and very low wattage

Look at this on eBay  http://www.ebay.co.uk/itm/221080916222


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## jameson_uk

Paul L said:


> My recommendation would be to ensure the canister filter isn't packed too tight, reduce hose length if possible, take off extention spray bar pieces leaving only three sections.
> 
> This is the circulation pump I've got no my 55 gallon tank , it's silent in operation and very low wattage
> 
> Look at this on eBay  http://www.ebay.co.uk/itm/221080916222


And back to where this started 
My original setup was with three sections and I had reasonable flow in half the tank but basically nothing in the other half.

Will do some experimentation this weekend.


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## Paul L

For what it's worth, I would recommend the Tunze pump. I'll try to add a video of the water moment in my tank with the filters switched off for you to see how good a job it does


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## jameson_uk

Paul L said:


> For what it's worth, I would recommend the Tunze pump. I'll try to add a video of the water moment in my tank with the filters switched off for you to see how good a job it does


Would be interested in video but still leaves the question if what is adequate.  I could add 10 pumps and power heads but this would be far too much.

I am thinking I need some surface agitation and some current inside the tank.  Would the surface agitation shown above actually do all the necessary gas exchange in a low tech setup?  The current and flow under the water could then be handled by pumps.  Must admit I was looking at the New NewWave 1.6 adjustable pump as that might be more flexible in the long run but it is all academic if there is not enough surface agitation


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## jameson_uk

Paul L said:


> It's easy to pack too much media in the Eheim classic canisters which could also slow the through flow. Is your filter tightly packed?


Not entirely sure 

I got the boxed media set (1l Mech and 4l substrat) for the 2217 and put all the EHFI Mech in then the blue sponge and then a fair amount of the substrat (there is still a fair amount left) followed by the white pad.
How much media should I have in there?


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## Paul L

jameson_uk said:


> Not entirely sure
> 
> I got the boxed media set (1l Mech and 4l substrat) for the 2217 and put all the EHFI Mech in then the blue sponge and then a fair amount of the substrat (there is still a fair amount left) followed by the white pad.
> How much media should I have in there?



The media trays both my filters are roughly half full, mostly Eheim substrat pro and matrix for biological, ceramic rings for mechanical, and of course the sponge pre filter. The top trays of both are topped with filter floss for last stage. 
The Eheim 2217 is a good filter and is rated for tanks bigger than your 180. My brother ran the thermo version on a 5 foot tank housing adult Oscars and Tin Foil Barbs very successfully for years. The head height isn't that great, so something has to be slowing the flow. Have either the inlet or outlet hoses got even the slightest kink? This would severely affect the throughput.


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## jameson_uk

Paul L said:


> The media trays both my filters are roughly half full, mostly Eheim substrat pro and matrix for biological, ceramic rings for mechanical, and of course the sponge pre filter. The top trays of both are topped with filter floss for last stage.
> The Eheim 2217 is a good filter and is rated for tanks bigger than your 180. My brother ran the thermo version on a 5 foot tank housing adult Oscars and Tin Foil Barbs very successfully for years. The head height isn't that great, so something has to be slowing the flow. Have either the inlet or outlet hoses got even the slightest kink? This would severely affect the throughput.


The 2217 is the Classic 600 (one of the round canisters).  I don't think there is a thermo version of this and there are no trays so the media is just piled in.

I was careful to avoid any kinks in the tubing and they are as short as they can be (allowing a little bit of movement for cleaning / adjustment).   Will check for kinks when I am cleaning over the weekend.


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## Lindy

I'd put a short spraybar on one side of the tank. 

Sent from my SM-G920F using Tapatalk


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## dw1305

Hi all,





Paul L said:


> It's easy to pack too much media in the Eheim classic canisters which could also slow the through flow. Is your filter tightly packed?





jameson_uk said:


> followed by the white pad.


I'd take the pad out and some of the mech media. They aren't very attractive but a sponge on the filter intake keeps debris out of the filter, and should improve flow. The Eheim pre-filter is horrible, but effective.





jameson_uk said:


> I know that I need surface agitation to make sure there is oxygen in the water but I know I don't want too much as this will get rid of the CO2 that the plants need (during the day anyway).


 I think low tech that having more surface agitation actually increases CO2 levels during the photo-period, because you have more gas exchange. The steeper the gradient between  atmospheric and dissolved gas levels the faster the rate of diffusion.

This means that as photosynthesis depletes the available CO2 it diffuses in from the atmosphere more quickly at the waters surface. 

The solubility of CO2 is much higher than it is for oxygen, but it only makes up 400ppm of the atmosphere, compared to ~21% for O2. 

It is difficult to measure dissolved gases, so a lot of "facts" are really just conjecture, we can use the diurnal variation in pH as a proxy for CO2/O2 (CO2 is an acid and oxygen a base). Somewhere there is a thread where "BigTom" measured pH through a diurnal cycle in a low tech tank with, and without, water movement. 





ldcgroomer said:


> I'd put a short spraybar on one side of the tank.


   I'd probably do the same. 

cheers Darrel


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## Lindy

If you want a prefilter allpondsolutions do one that you put in line before your external. I've just fitted 1 to each intake tube on my eheim thermo filter as it will be easier to clean them every week than do battle with the eheim. It might drop your flow a bit though.

Sent from my SM-G920F using Tapatalk


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## Daveslaney

Put your drop checker a couple of inches above your substrate level on your front glass,leave it there for a day.If you get a colour change this will tell you if your flow is enough to take co2 down to your carpet plants.


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## jameson_uk

dw1305 said:


> Hi all,I'd take the pad out and some of the mech media. They aren't very attractive but a sponge on the filter intake keeps debris out of the filter, and should improve flow. The Eheim pre-filter is horrible, but effective.


Did I not mention I have the Eheim pre-filter already installed 
I put this in a week or so ago as I figured the amount of plant crap was going to start gunking up the filter sooner rather than later.   I cleaned the sponges after a week and they were manky.  Could the pre-filter be reducing the flow?
Do you the mean the blue mesh or white fine pad?  I am looking to add a Purigen pouch in there when I clean and will take all the media out so can add back in what is necessary.   How much media do you think should be in the filter (especially given some mechanical filtration is now being done by the pre-filter) ?



Daveslaney said:


> Put your drop checker a couple of inches above your substrate level on your front glass,leave it there for a day.If you get a colour change this will tell you if your flow is enough to take co2 down to your carpet plants.


I don't have a drop checker nor carpet plants


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## jameson_uk

I was out getting a bit of fish food and noticed LFS had the Newa Wave 1.6 adjustable circulation pump reduced to £25 so figured I would pick one up.
Stuck it in the tank and this made quite a difference.   I could see all sorts of bits drifting.  In fact I added it in the middle of the largest amazon sword and the flow on the leaves actually uprooted it.

Video is still uploading but this shows the flow now with all the plants moving.   This is after I shortened the spray bar to four bits (I thought I did three but turns out I can't count )
Will the fish be OK with this kind of flow?   The corys actually started schooling which they had not really done before and seem to be unfazed by it, the dwarf rainbowfish just hid but I think will be OK with it but the black neon tetra worry me.   There is quite a bit of flow into the back of the pump and I have seen the tetra getting here and then struggling to get out.   It has also sucked all the amazon frogbit across the tank into the space above the pump.

This is on the lowest setting (800 l/h; it goes up to 1,600 l/h).

What is the flow like in other people's low tech tanks?


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## Daveslaney

Lol sorry reading to many posts at one time


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## Paul L

Flow from the spray bar looks decent now.
Your fish are loving the flow from the circulation pump!
Seems you've found a solution!


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## jameson_uk

Paul L said:


> Flow from the spray bar looks decent now.
> Your fish are loving the flow from the circulation pump!
> Seems you've found a solution!


Except the dwarf rainbowfish who are cowering in the corner...  given they are meant to come from flowing streams I hope they will get used to it.  

Will show flow properly tomorrow when I am brave enough to open the filter


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## jameson_uk

OK so today I

Cleaned filter media
Took out a couple of handfuls of substrat pro
Added a bag of Purigen
Replaced a little bit of tube between the filter and valve which had a little kink
Now I may have two much flow....

or with a longer bar


I have left it with the shorter bar at the moment but I have noticed some of the frogbit being squashed against the glass opposite the spray bar and being dragged a little under the water.   Does this flow look better / too strong and I keep thinking about this from a physics perspective and wondering what is actually happening to the flow.   Without the circulation pump I guess I am now getting the same flow as I drew up in the first post but I am potentially creating some kind of vortex by having the circulation pump pushing across this movement?

Also how much of each media do I really want?   I have 1 litre of Ehfimech then a blue coarse sponge followed by about 3.3 litres of substrat pro (well I have 700 ml of media left and I think the media set comes with 4l) followed by a white fine pad and 100ml pouch of Purigen.


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## dw1305

Hi all, 





jameson_uk said:


> Could the pre-filter be reducing the flow? I put this in a week or so ago as I figured the amount of plant crap was going to start gunking up the filter sooner rather than later.


 Yes it will, but it is much better to stop the plant leaves etc ending up in the filter. 

It had never occurred to me that people would use their external filter as a syphon, in terms of biological filtration it is a recipe for disaster, unless you are extremely fastidious about cleaning the filter. The same applies to having both aerobic nitrification of ammonia and anaerobic denitrification (of NO3) in the same canister filter, it is possible but the likelihood of the whole filter becoming anaerobic should preclude it as an option. 

Biological filtration and dissolved oxygen are different from nearly all factors in that they  have to be right 100% of the time, and what people often don't realize is that they are implicitly linked. There is a misconception that you need a huge volume of filter media to achieve biological filtration, and that the Biohome, Siporax, Coco-pops (which are good media) you use has to have special properties,  but it isn't actually true. What limits biological filtration, in nearly all circumstances, is dissolved oxygen. Basically if your oxygen supply exceeds your oxygen demand, you are sorted. Have a look at <"Plecoplanet:  aeration and dissolved oxygen..">. I wrote it about 10 years ago specifically for Plec keepers, and it has had a few homes, but it is applicable to nearly all freshwater aquariums.  





jameson_uk said:


> I have 1 litre of Ehfimech then a blue coarse sponge followed by about 3.3 litres of substrat pro (well I have 700 ml of media left and I think the media set comes with 4l) followed by a white fine pad and 100ml pouch of Purigen.


You don't need the mech media, or the fine white pad. When you have the pre-filter in place it is going to do your mechanical filtration. 





jameson_uk said:


> Does this flow look better / too strong and I keep thinking about this from a physics perspective and wondering what is actually happening to the flow. Without the circulation pump I guess I am now getting the same flow as I drew up in the first post but I am potentially creating some kind of vortex by having the circulation pump pushing across this movement?


 It looks fine, you ideally want laminar flow with the pumps facing in the same direction because that is the most efficient way of circulating the water, basically it increases the effective gas exchange surface area. 





jameson_uk said:


> There is quite a bit of flow into the back of the pump and I have seen the tetra getting here and then struggling to get out. It has also sucked all the amazon frogbit across the tank into the space above the pump.


Your surface plants will end up in the area with lowest flow. I've never used this style of circulation pump, I've only used a powerhead and sponge, but I would have worries about fish being sucked in, hopefully some-one who uses them will be able to tell you that they are fish safe.

cheers Darrel


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## Paul L

The spray bar flow looks much improved.
I would've removed the mechanical media instead of the biological though.

Regarding Darrel's comment about the circulation pump, as long as the fish can't get into the unit they'll be fine. They might take a while to get used to the extra flow but they'll thank you for it soon !


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## jameson_uk

dw1305 said:


> It had never occurred to me that people would use their external filter as a syphon, in terms of biological filtration it is a recipe for disaster, unless you are extremely fastidious about cleaning the filter. The same applies to having both aerobic nitrification of ammonia and anaerobic denitrification (of NO3) in the same canister filter, it is possible but the likelihood of the whole filter becoming anaerobic should preclude it as an option.


OK stupid Newbie question but.... isn't this how most setups are configured?   I guess most people who come back from LFS with a tank probably end up with an internal filter doing just this and those that do get an external one with have it as their only filter     I guess in an ideal world we would have some sort of wet & dry filter as well but is this just better rather then "a recipe for disaster" ?
Also how do you split the NH4 => NO2 and NO2=>NO3 processing?   Is this by simply providing a bigger stronger colony that has access to oxygen to do the aerobic bit (meaning no food left to develop elsewhere) ???



Paul L said:


> The spray bar flow looks much improved.
> I would've removed the mechanical media instead of the biological though.


That is what I meant to do but was an auto pilot so only thought about this whilst putting the pump head back on.   Next time I clean the filter in six weeks or so I will remove the mech media and add the remaining substrat pro I have left over.


> Regarding Darrel's comment about the circulation pump, as long as the fish can't get into the unit they'll be fine. They might take a while to get used to the extra flow but they'll thank you for it soon !


They do seem to be getting used to it and from what I can tell they know how and where to get out the flow but are actively choosing to be in it (the corys in particular but also the rainbows who seem to school when doing it and occasionally the tetras).

Will attempt some different configurations in a few weeks as the rainbows seem to get very scared everytime there is a change (and there have been a few recently) so will let them settle for while first.


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## dw1305

Hi all,





jameson_uk said:


> OK stupid Newbie question but.... isn't this how most setups are configured? I guess most people who come back from LFS with a tank probably end up with an internal filter doing just this and those that do get an external one with have it as their only filter


I think you are right, if you don't have plants (and a substrate) you are entirely reliant on the filter bacteria/archaea for nitrification. There are then three potential methods for the removal of NO3-.

Chemical media, such as a specific anion exchange resin
Water changes with water lower in nitrates.
and anaerobic de-nitrification of NO3- and out-gassing N2 gas.
You obviously can keep, and breed fish, successfully using "microbe only" filtration, but it is a system with a single point of failure (the filter) and very little resilience.

In my experience successful fish keepers, who don't have planted tanks, often fail to fully appreciate how skilled they are. 





jameson_uk said:


> I guess in an ideal world we would have some sort of wet & dry filter as well but is this just better rather then "a recipe for disaster" ?


Plants are the answer. There is a <"negative feedback loop">, where enhanced nitrogen levels lead to enhanced plant growth, which leads to lower nitrogen levels. An increase in ammonia in a "microbe only" filtration system is likely to lead to fish death and increased ammonia production, which leads de-oxygenation which leads to fish death etc.

If I didn't have plants I would definitely have a wet and dry trickle filter, and the "Rolls-Royce" of filters is a planted trickle filter. If you have plants, and specifically some with aerial portions, you have a system which is much more efficient and resilient. As a general rule "plant/microbe systems" are about  an order of magnitude more efficient than "microbe only" systems.

There are number of reasons for this, one that people often fail to grasp is that plants are massively net oxygen producers, basically for every molecule of CO2 used in photosynthesis a molecule of oxygen (O2) is produced.

At light compensation point CO2 use and oxygen evolution is in balance, but during active photosynthesis plant growth is a measure of the carbon capture. At the end of the photo-period usually both tank water and internal plant tissues are saturated with oxygen and it is overwhelmingly this internal oxygen store that is used for plant respiration during the dark period.

In an <"emergent plant"> there is oxygen transfer to the substrate, which greatly increases the area of the zone where nitrification can occur.





jameson_uk said:


> Also how do you split the NH4 => NO2 and NO2=>NO3 processing? Is this by simply providing a bigger stronger colony that has access to oxygen to do the aerobic bit (meaning no food left to develop elsewhere) ???


You don't really need to, they are both aerobic processes. We now know that <"a much greater range of organisms"> convert ammonia to nitrite, but the energy transfer is still <"the same">, with oxygen consumed and bio-acidification (you've gained 4H+ ions) occurring.






A lot of the discussion in fish keeping circles is about "cycling" and ammonia and the idea that the nitrifying organisms will die if they don't receive a constant dose of ammonia, <"but it isn't really true">. Oxygen is the prime metric, which is why scientists use BOD  (Biochemical Oxygen Demand) as their measure of organic pollution.

cheers Darrel


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## jameson_uk

OT but interesting 


dw1305 said:


> Hi all,I think you are right, if you don't have plants (and a substrate) you are entirely reliant on the filter bacteria/archaea for nitrification. There are then three potential methods for the removal of NO3-.
> 
> Chemical media, such as a specific anion exchange resin
> Water changes with water lower in nitrates.
> and anaerobic de-nitrification of NO3- and out-gassing N2 gas.


My chemistry always was pants but after researching the nitrogen cycle (documented as you say by fish keeping circles) I was thinking that the only real way of reducing Nitrates in a non-planted was through water changes.
Does this de-nitrification (which I believe is biological) actually happen normally (in any great volume) or is this something you need to setup?  I have read about deep sand beds, but is there not too much oxygen in a standard filter to allow this to take place?



> Plants are the answer. There is a <"negative feedback loop">, where enhanced nitrogen levels lead to enhanced plant growth, which leads to lower nitrogen levels. An increase in ammonia in a "microbe only" filtration system is likely to lead to fish death and increased ammonia production, which leads de-oxygenation which leads to fish death etc.


Is this not with the caveat of plants with the right balance of CO2, light and nutrients?   My understanding is that in a low tech setup like mine, the plants will take up very little nitrate as this needs them to take in Carbon and metabolise?  As I guess Carbon will be by far the limiting factor in my tank will the low level plants I have actually make any impact on Nitrates?

Amazon Swords
Lilaeopsis Brasiliensis

Crypt
Rotala Rotunifolia
Bacopa Caroliniana

Vallisneria 

Anubias

Java Fern
Java Moss
I also added some Amazon Frogbit as the fish I have wanted some floating plants but I guess these have the possibility to process more Nitrates as they can take CO2 from the air but then these are probably limited by nutrients?
I put some root tabs under the swords a while ago and I have recently started dosing Flourish once a week if this will make any difference.

I mainly bought the live plants because I thought they looked nicer than fake ones and chose the ones I did because they would survive in a low tech setup.  I am interested in what the impact might be in a setup like mine.


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## dw1305

Hi all, 





jameson_uk said:


> Does this de-nitrification (which I believe is biological) actually happen normally (in any great volume) or is this something you need to setup? I have read about deep sand beds, but is there not too much oxygen in a standard filter to allow this to take place?


 It will occur in nearly all substrates to some degree. Usually only the top layer of the substrate, and the zone immediately around the root (the rhizosphere) will be fully aerobic, deeper in the sediment there will be a zone of fluctuating oxygenation, and after that anaerobic zones where reduction reactions will take place. Although these zones of fluctuating, and negative, REDOX potential will lead to the loss of fixed nitrogen, they will make other minerals (like iron (Fe)) available.  





jameson_uk said:


> Is this not with the caveat of plants with the right balance of CO2, light and nutrients? My understanding is that in a low tech setup like mine, the plants will take up very little nitrate as this needs them to take in Carbon and metabolise? As I guess Carbon will be by far the limiting factor in my tank will the low level plants I have actually make any impact on Nitrates?


 No, there really aren't any caveats.

Floating, or emergent plants vastly increase the ability to deal with bioload, because they have access to atmospheric levels (400ppm) of CO2,  but submerged plants will still very effectively deplete NH4 and NO3. One reason for having floating plants is just that they are easier to harvest. 





jameson_uk said:


> I mainly bought the live plants because I thought they looked nicer than fake ones and chose the ones I did because they would survive in a low tech setup. I am interested in what the impact might be in a setup like mine.


 There is a <"huge amount of scientific literature"> on the efficiency of plant/microbe filtration, along with a <"growing body of evidence"> (based on RNA profiles) that microbial filtration is carried out by a much wider range of organisms than was traditionally thought, but very little of this has filtered through to the more traditional parts of the fish keeping community, where plants are often regarded as merely decoration, and endless hours are spent discussing ammonia and cycling.

I maybe cynical, but I think that certain parts of the fish keeping industry are very interested in keeping people in the dark about the key factors in successful fish keeping, possibly so that they can carry on selling them all sorts of "magic bullets".

cheers Darrel


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## jameson_uk

OK so back to flow...
I am reading into this that ideal flow might be front to back laminar flow creating the circular flow pattern above but across the whole tank.
In terms of current I ideally want all the plants swaying .

This sounds sensible in terms of distributing nutrients, heating etc but one thing that still confuses me is the actual circulation.   I guess for this I would ideally have flow the length of the tank pushing all the detritus and water over to the intake meaning that it was not just the same water getting circulated.   This however is contradictory to the laminar flow above....


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## jameson_uk

OK tank has been running like this for a few weeks and the plants on the opposite end of the tank to the spray bar look a lot healthier (Java Ferns have spores and new leaves, vals look a lot healthier and the Anubias has grown after being fairly static since I had it so all good there.

The amazon swords near the spray bar actually look worse and I have noticed a build of up detritus under the spray bar at the back of the tank (I suspect this is lack of nutrients so I will put to root tabs under them tomorrow but they were a lot healthier for several weeks with just the spray bar and no flow pump.

I guess the flow will currently look like from the front


 
and from the top


 
So this is creating turbulence and stopping the flow from the spray bar hitting the front glass, rolling across the substrate and back up the back glass.

I was wondering whether it would be worth looking at putting the spray bar on the same side as the inlet which could be across the side like
Front


 
Top


 
Or vertically in front of the intake
Front


 
Top


 

The vertical spray bar concerns me in terms of not providing any surface agitation and potentially turning the tank into a whirlpool but the horizontal spray bar would just be creating a vortex in the other plane?

The flow pump is doing a great job of moving stuff from the substrate towards the filter but the current flow setup means that when the filter / pump are on that food is sucked to the bottom really quickly  so fish either get to eat from the surface or the substrate (seems to take less than a second for even slow sinking pellets to hit the floor).   The pump also creates quite a lot of flow that some of the fish appear to like swimming in.

I currently have a spare powerhead (rated at 270 gph) some spare spray bar, the flow pump and some time tomorrow to experiment...   One thought I had was removing the flow pump and attaching the extra spray bar to the powerhead across the back of the tank to give back to front laminar flow.

Any thoughts on whether I should just leave as is or attempt one of the options above?


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## jameson_uk

Still not entirely happy with the flow as have found I am getting large build ups of gunk in the back right corner (near the inlet) which are a right pain to clean as there area a lot of root plants there and it is behind the large driftwood.

The flow from the Ehiem even with the shorter spray bar is still not as good as that posted by @ian_m (I know his filter has a larger rated flow and Eheim tend to overegg their figures anyway) but his flow seems to be nearly hitting the over side of his tank where as mine if only getting about half way across.

I was considering going back to the extended spray bar with lower flow and moving the flow pump to augment it (and add a second on the other side of the tank) so the actual flow would largely be generated by the powerheads and the filter just handling turnover.

The other option is to add a second 2217 on the other side but trying to avoid this if possible.


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## Christos Ioannou

I have had a similar issue and I will try to overcome it with one of these


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## KipperSarnie

Not sure if this is worth a new topic but it seems to fit in here just about right.  (Not really sure it's the right forums either)

5x2x2 tank for Uaru, plenty of driftwood (Twisted Hazel) & a few good size pebbles on a JBL Manado base.
Plants are Echinodorus Bleheri & Anubias Barteri & ANUBIAS Lanceloto.  (Hopefully they won't be to the Uaru's taste!)
Lighting is TMC Grobeams so I can fine tune the lighting for the fish & plants if not eaten.
Filter is TetraTec EX 1200+.

My problem is too much flow across / down? the tank.
The spray bar is fitted across one 2ft end.
I want to keep the filter working at max flow if possible.  Not sure that I need to though?

I've tried various angles for the spray bar outlets, straight down turns that end of the tank into a maelstrom!

Anybuddy have any thoughts on this before I drill bigger holes in the spray bar to relieve the force?


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## tim

KipperSarnie said:


> Not sure if this is worth a new topic but it seems to fit in here just about right.  (Not really sure it's the right forums either)
> 
> 5x2x2 tank for Uaru, plenty of driftwood (Twisted Hazel) & a few good size pebbles on a JBL Manado base.
> Plants are Echinodorus Bleheri & Anubias Barteri & ANUBIAS Lanceloto.  (Hopefully they won't be to the Uaru's taste!)
> Lighting is TMC Grobeams so I can fine tune the lighting for the fish & plants if not eaten.
> Filter is TetraTec EX 1200+.
> 
> My problem is too much flow across / down? the tank.
> The spray bar is fitted across one 2ft end.
> I want to keep the filter working at max flow if possible.  Not sure that I need to though?
> 
> I've tried various angles for the spray bar outlets, straight down turns that end of the tank into a maelstrom!
> 
> Anybuddy have any thoughts on this before I drill bigger holes in the spray bar to relieve the force?


Could you extend the spray bar and run it across the back wall of the tank facing forward ?


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## KipperSarnie

tim said:


> Could you extend the spray bar and run it across the back wall of the tank facing forward ?



Never thought of that, I need to delve into my "Lucky box" for elbows & pipe to suit.


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## Coys

I had a similar problem with the Eheim extensions when I tried extending the spray bar along the back of my 240l. I solved it by making a DIY spray bar from acrylic and drilling much smaller holes than those in the Eheim extensions, which I think are far too large.


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## KipperSarnie

Coys said:


> I had a similar problem with the Eheim extensions when I tried extending the spray bar along the back of my 240l. I solved it by making a DIY spray bar from acrylic and drilling much smaller holes than those in the Eheim extensions, which I think are far too large.



Would that not reduce the flow rate?
I'd thought of going with bigger holes!

The Uaru I have at present are only about 4/5cm but from experience they grow to 25/30cm with a mainly vegetable diet so I will need to keep the filter at full chat as they grow.


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## sciencefiction

It's already been suggested, but have you tried the spraybar on the short side of the tank blowing the length? You don't need amounts of flow that make your fish cower in corners. You just need the flow to blow the water in the desired pattern.  I am not sure what type of media you've got in your external but I'd suggest use medium sponges as mechanical media, not floss, and also put a sponge on the intake as a prefilter.
The solution is obviously a second external. It's a good idea, even for redundancy.

In my 5f tank I ran the spraybars both across the long and the short side at some stage. When I moved them on the short side I stuck them in a row of three spraybars one under the other and it did the job to blow all the way to the other side, around the driftwood there and move the gunk back to under the spraybars 5f distance back. There I had to siphon it from time to time but the point is, it didn't gather anywhere else.

When I had the spraybars along the length of the tank, all the gunk settled out the back across the whole length of the tank so it was difficult to reach. I don't normally siphon planted substrate but you do want to remove big bits and there's plenty over the years...


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