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???)

 

[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.

 

[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.

 

[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.

 

[jameson_uk]

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

 

[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.

 

[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?)

 

[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?

 

[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.

 

[jameson_uk]

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?

 

[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.

 

[Andy Thurston]

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.

 

[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.

 

[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?

 

[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

 

[jameson_uk]

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.

 

[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

 

[jameson_uk]

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

 

[jameson_uk]

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?

 

[Paul L]

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.