# Co2 Fluctuations and BBA



## AverageWhiteBloke (29 May 2010)

Can someone explain what is meant by fluctuations in co2 and BBA? I have been battling with BBA for a while combating it with keeping my co2 on target at lights on time and easy carbo at the recommended dosage. I run my co2 24/7 as I have no solenoid and with work commitments I am often not at home to be knocking it on/off.
So by fluctuating do you mean going from enough co2 to not enough or enough to too much or both? if that makes sense   I guess through night and early morning my levels are high but then ok lights on then the rest of the day so can the fluctuation from too much to good levels promote the BBA?


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## ceg4048 (29 May 2010)

Hi,
    I appreciate that conceptually, it's often difficult to get ones head wrapped around CO2 instability. This happens because we have a limited understanding of how CO2 is processed and used inside the plant.

It's less a matter of not enough/too much, but rather a matter of gas availability whose mass oscillates above a certain value.

In order to get a better picture, first have a read of the recent thread http://ukaps.org/forum/viewtopic.php?f=19&t=11320 in which some insights are provided into the chemistry of CO2 usage.

So for a given lighting level the plant requires a specific CO2 level. Lets use some imagination and pretend that we have made a "Contract" with the plant to deliver a specific daily concentration level. We can oscillate slightly around this specific concentration level but at some point, if the CO2 concentration "excursion" is too far either below or above the contract level this causes the plant to decide that it must re-configure Rubisco enzyme production to account for the change in concentration level.

If we were to deliver a concentration level lower than the original contract level -  but held that lower level constant, the plant might suffer short term damage but might make the enzyme adjustments. In a couple of weeks it would recover. As long as this new lower level is not acutely low, the only penalty would be slowed growth rate and perhaps a little algae here or there.

If we were to deliver a concentration level higher than the original contract level - but held that higher level constant, the plant would simple adjust the level of Rubisco to account for the higher level and after a few weeks growth rate would simply increase.

Remember, we're talking about a matter of weeks to make the adjustments to new CO2 levels. Each time the concentration excursion breaks the contract, an enzyme adjustment is triggered. Concentration excursions that occur frequently throughout the day causes havoc with enzyme production because a different enzyme level is commanded at each excursion.

On top of that, each time the excursions falls below the original contract level for the lighting, internal damage is caused in a way that can almost be described as radiation poisoning, because high energy electrons (elevated to higher energy due to photon bombardment from the light), which are supposed to be involved in reactions with CO2, have nowhere to go, so they smash into nearby cells causing ionization of the cells molecular structure.

There are a couple of ways concentration excursions can occur:
1. A shoddy regulator may oscillate it's output.
2. Poor flow in the tank could actually affect the concentration levels either locally or unilaterally.
3. Low basic levels and low injection rate might cause the concentration levels to fall during the day simply by the uptake of the plants themselves, especially if you have a high plant mass.
4. So called midday bursts increase the photon bombardment, thus increasing both the uptake and the electron activity. If there is insufficient CO2 for the burst energy level then this counts as a downward excursion.
5. Uncontrolled out-gassing due to filter or other causes such as surface disturbance and so forth can cause levels to drop.
6. Ph Controllers which vary the injection rate to maintain pH cause excursions by default.

These are just the popular ways I can think of. There are probably as many ways as their are the number of hobbyists. Each way by itself may not be too bad, but combinations are additive. 

In your case, it may be a matter of increasing the injection rate to allow for the consumption and to help stabilize the level. You may need to look at doing a good trim to lower the biomass. You may need to rework the flow distribution method, perhaps remove large hardscape items, for example. You may need to lower the light or to cut out midday bursts and so forth.

Hope this helps.  

Cheers,


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## chris1004 (30 May 2010)

Hi Clive / all,

Thanks mate for such a brilliant description in both this thread and the one linked to, even I understood it and will no doubt refer back to it often in the future.

Going backwards a bit to the OP and having suffered at the hands of BBA myself I must say that in my limited experience thus far I have found this particular strain of algae very hard to eliminate completely. I've had it grow on all manner of hardscape within the tank, filter outlet pipes, bogwood, rocks, gravel as well as the plants themselves. It sometimes seems that you only have to take your eye off the tank for a week or two and its back.

It took me a while to realize that the tank is an ever changing entity because the plant mass is ever changing. But once you do and learn how to react accordingly things become much clearer.

Regards, Chris.


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## AverageWhiteBloke (30 May 2010)

Yeah thanks even a dummy like me gets the jest of that   That answer has also pointed out another mistake I have been making by accident  8) I have three light tubes and when co2 levels are not optimum I have been switching one and sometimes two of them off now and again to compensate, reading your advice that would mean that not only was I not keeping my side of the providing the co2 deal for the given lighting the plants were not sure of what the deal was right? 
Sort of confusing them has too how much Rubisco to produce in the first place. I guess that having the same lighting constant will tell the plants what to expect, the plants will react to that and then I need to provide them with what they need co2 wise and nutrients to live in the lighting conditions I have created. 
My tank is moderately planted and I did have a tendency to let it grow wild, the feed from the filter is in one corner and I can't attach a spray bar but I notice as long as I keep them clipped out from the path of the outlet I can get the majority of plants swaying and the addition of a small internal filter that connects to a co2 reactor helps push water round the front to them hard to reach places. I don't have any hardscape items just a small piece of wood front centre which doesn't really get in the way of any flow.
I am currently injecting quite a lot of co2 in comparison to other tanks with similar lighting being 70watts of T8's over 155ltrs, I have a DIY set up putting 2/3 BPS into a reactor connected to an internal as well as pressurised connected to a nano diffuser which I use to compensate the inconsistencies in the DIY like when I'm setting off a fresh batch on one of the two bottles. This I put down to my wet/dry filter de-gassing which unfortunately I'm stuck with for now, I try and reduce this as much as possible by filling the media chambers right to the top so the spray bar is running straight into the media rather than dropping down on to it and keeping my tank water levels as high as possible to reduce surface disturbance. I'm investigating somehow connecting the power head to some tupperware containers where the media baskets are which I could seal from the atmosphere but that's another story   In the long run I think I might butcher my systemised filter and switch to a decent canister I don't think I will be selling this set up any time soon anyway.

So my lime green DC is telling me that the right levels of co2 are trying to escape from my column and I need to make sure that they hit every leaf on the way past. Armed with this new knowledge I will see how that goes over the next few week. I'll keep up the easy carbo until the BBA has gone if it ever does and try and keep the flow good by clipping out stuff that slowing down the circulation and adjusting it's path  If it clears and I and my new approach returns more algae then I suppose I could knock a light tube out of the equation and see if that helps leaving less room for error.
It amazes me how much planted tanks can draw comparisons with body building, like eating certain things at the right times and your body taking a couple of week to naturally react to the change. There are a few I could mention but I suppose it's because they are one and the same manipulating the natural metabolism to get the required results.

Anyway off topic there   so can I ask a possibly stupid question, does BBA grow just in the tank generally or does it grow predominately where the areas of bad circulation are? Just wondered as there is an area front corner that is worse affected which I have assumed to be possibly down to daylight from a near by patio door. If low circulation areas grow the BBA then I could try and make sure I get better circulation to these areas if possible.


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## ceg4048 (30 May 2010)

Hi,
   BBA will grow wherever it's triggered and can then spread to surrounding areas. As Chris mentioned, it's very difficult to eradicate completely as it will often grow as small patches on hardscape and even on filter tubes. As long as it doesn't grow on the plants you'll be doing well. DIY CO2 can contribute greatly to the triggering of BBA because it's output generally is unstable. Temperature, yeast populations and so forth affect the gas production rate. This is one area you might want to look at. If you have pressurized system then there is really no need to also have a DIY attached. I would say this might have a bigger impact than the type of filter.

Another thing to keep in mind is that even when you fix the conditions that trigger BBA, it won't just automatically go away. You still have to scrub and manually remove, or use Liquid Carbon products to clear existing growth away.

Cheers,


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## Mark Evans (30 May 2010)

ceg4048 said:
			
		

> Hi,
> I appreciate that conceptually, it's often difficult to get ones head wrapped around CO2 instability. This happens because we have a limited understanding of how CO2 is processed and used inside the plant.
> 
> It's less a matter of not enough/too much, but rather a matter of gas availability whose mass oscillates above a certain value.
> ...



Clive, great read man!


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## AverageWhiteBloke (3 Jun 2010)

Thanks Clive I have tried using just the pressurised with a glass ceramic diffuser and with a spiral ladder type diffuser but unless I used what I would think to be an unreasonable amount of co2 I couldn't get my DC to optimum target and hold it. The problem with the existing filter system is that not only does it de-gas because of the lack of piping it also stops me using some of the in-line type diffuser's which seem to be more effective holding the co2 in suspension until most of it has been diffused and the choice of most people in this board.

Apologies for the picture quality mobile phone pics I thought I'd put them up to make you clear of what I'm working with. 


Water is pulled up with power head on left hand side.

Sprayed over media boxes

Gravity fed and spread out into the aquarium on the right hand side. On the right hand side out of shot in the top picture is the glass diffuser under the outlet and a plastic diffuse fed off the diy connected to an internal which points round the front glass. As you can see the filter in the lid is fail safe so if it were to fill up with water it would run into the outside chambers and back into the tank. I would have to make cut outs for an external canister which would render the built in filter system useless. I am only using a 600grm cylinder at the moment but I have a 2kg co2 FE that I found in a skip   not sure if there's anything in it it was out of some flood damaged property so I'm looking at buying a regulator and setting this up to keep costs down.
I am quite methodical with the diy I alternate changing bottles which I know take 24 hrs to get full output, to try and compensate for this by making the mix at night when the co2 is not needed and the next morning I switch on the pressurised, usually when I get home from work the diy is back in full swing and I gradually ease back the pressurised. I am aware this is not ideal.


> We can oscillate slightly around this specific concentration level


I'm hoping I'm within tolerance using this method but I might have to throw some money at it   

Other than that I'm getting some results no real sign of deficiency, just a bit of BBA round some edges and hard scape of which most has gone after another full week of EC dosing.

With Ukaps help I'm getting there though  8) I might even be able get past making them grow and think more about scaping but don't hold your breath   enjoying all aspects of it anyway.

Thanks again.


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## Anonymous (3 Jun 2010)

In the future if you plan not to use EC you should get rid of that gravel and any decoration that is not chemically stable if you don't want BBA issues in your tank. Life afterwards will be a lot easier, trust me .


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## AverageWhiteBloke (3 Jun 2010)

Not sure what you mean, the gravel is inert mixed with aquarium sand and the only other thing in there is a piece of bog wood which may leach a little tanin in there can you explain your reasoning please.


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## bigmatt (3 Jun 2010)

Hi there,
Just to let you know I have an AR980 and run an external on it.  A small external (i use a Fluval 203) or any with 12mm tubing will do the job and fit into the tank with minimum cut outs whilst retaning the trickle filter.  Having said that i'm not running CO2 and can see that it's a hell of a job to circualte CO2 properly. As the filter input is a single output i'd probably think about a pressurised CO2 system (well worth the investment!) with a splitter, three or four diffusers and supplemental powerheads.  I knowit's costly but it's the only way i can think of to get CO2 distribution short of buying a hugely powerful filter (it'd need a biggie - something like an FX5 -  to power the CO2 through the depth and height of the tank).  
In my case i'm not running CO2 on the big tank, and get my "high-tech" fix on my smaller tanks to save on cost as much as anything else.  The AR980 is going to be changed to a low tech system with Angels when i get round to it.
In summary (why use 4 words when 400 will do!) i'd bin the CO2 on a tank this size and configuration - i can only see it being an absolute nightmare to get it right, and even then you'd have to chuck some serious wonga at it to get the results.  For a much smaller investment you can build either a low tech planted (which can still be amazing!) or a high tech nano, or probably both!
Hope this helps - i've got a pretty tight budget too and know exactly where you're coming from!
Matt


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## ceg4048 (4 Jun 2010)

AverageWhiteBloke said:
			
		

> Thanks Clive I have tried using just the pressurised with a glass ceramic diffuser and with a spiral ladder type diffuser but unless I used what I would think to be an unreasonable amount of co2 I couldn't get my DC to optimum target and hold it. The problem with the existing filter system is that not only does it de-gas because of the lack of piping it also stops me using some of the in-line type diffuser's which seem to be more effective holding the co2 in suspension until most of it has been diffused and the choice of most people in this board.


Well, I think there are a couple of things going on there. Certainly, having a solenoid will help with stability. Also, Ed Seeley has a thread showing how to build a cheap DIY external diffuser out of simple PVC piping. It might be worth adding an auxiliary second hand filter and connecting it to the diffuser as a dedicated system. That would mean more hood drilling though, so that might not be ideal.

I also think your scape is not helping you here. You've some very large swords that block flow and the Vallis also are very high drag.
As regards the DIY, even after waiting 24 hours, the yeast population accelerates, which accelerates the CO2 output. The population then levels off and then declines, so it really can never be thought of as being stable, except for possibly a short time in the population profile.

Anyway, it doesn't look too bad to me. There is insufficient resolution in those images to illustrate the BBA. The plants are otherwise healthy so maybe try a few different plants, perhaps trade the swords for some more slender stems, or perhaps prune more heavily.

Cheers,


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## Anonymous (4 Jun 2010)

You know if your gravel is inert or not if you had bba on it or on the base of your plants, if not then it should be ok.
Usually in shops you'll find industrial gravel, washed and with some plants or fish pictures on the bag, that doesn't mean that is "algae safe" . Anyway in the future try to aim for porous gravel the plants grow healthy in it and you shouldn't have algae problems, and try not to mix it with sand so the roots could "breathe".


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## AverageWhiteBloke (4 Jun 2010)

> Just to let you know I have an AR980 and run an external on it. A small external (i use a Fluval 203) or any with 12mm tubing will do the job and fit into the tank with minimum cut outs whilst retaning the trickle filter



Mines a AR850 Matt which is slightly smaller, I have a Hydor Prime 10 360lph which I could utilise left over from a previous tank which I could set up an independent pressurised system as Clive suggests. I would be interested to know where you made your cut outs if you have pics. When you say retaining your trickle filter do you mean running alongside the canister or you could still go back to it if you did away with the canister?



> I also think your scape is not helping you here. You've some very large swords that block flow and the Vallis also are very high drag.


The good thing here is my understanding of what's going on in there is improving after your reading your post    Last night before checking this thread I looked into the tank and thought, right I have a target DC (generally) so the other thing I need to look into is circulation and availability and came to the conclusion that would be best get the Amazon's out of the way of the outlet and get Vallis below water level, the Vallis causes a still area behind them on the surface which was causing what looked like a bit of Staghorn on the Vallis itself at the top so they got a good pruning last night which has improved high level water circulation. It has to be said though that picture was probably at the height of my bio mass I do my WC and pruning tomorrow so would usually have a lot less plants in it. This time I am going to be merciless with the pruning and may even do away with a couple of the Amazons. I just liked the look of the Vallis spread over the surface but it is causing problems.


> That would mean more hood drilling though, so that might not be ideal.


I'm at the point of no return I guess Clive, I think I'm making the mistake of making the plants adapt to my tank which should be the other way round. When I find where Matt made his cut outs I will do the same and like you advised try and get an independent co2 system running with better diffuser. I don't think the de-gassing is as bad as I first assumed   With my mediocre Ad-hoc  co2 set up I'm keeping target as long as the amount of co2 injected is stable so a better set up would acheive better results. I have the FE already, regulator and reactor so it's not going to cost much more to put all this stuff together.


> Anyway in the future try to aim for porous gravel the plants grow healthy in it and you shouldn't have algae problems, and try not to mix it with sand so the roots could "breathe".


Noted thanks, on water change day I do have a rake about with the sand to get the bubbles out I hope that will help with loosening it up for roots as well.


> Anyway, it doesn't look too bad to me. There is insufficient resolution in those images to illustrate the BBA


That's the problem with EC you never actually know whether the co2 set-up is right or the EC is masking my mistakes   I will try and get some better pics with my wife's cam tomorrow after the WC and clip out, her cam is half decent but photography isn't my strong point.


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## bigmatt (4 Jun 2010)

Haven't got any pics at the mo and away for a few days so i'll try and send some early next week.  Cutouts are basically on the left hand "dry" chamber where the powerhead pumps up - Small cutout at the back to get the tubing in, then the pre-existing holes accomodate a filter intake, and the filter outlet can be passed into the same chamber, with then a small cutout in the left wall of the filter trough above the waterline, and running the water back in therough the trickle filter.  To avoid off-gassing i also have successfully used a couple of 90 degree elbow peces and ran a spraybar across the tope of the tank. The trick is in having enough elbow pieces and tubing to make it work!


> I think I'm making the mistake of making the plants adapt to my tank which should be the other way round


A valuable lesson!    


> I have a target DC (generally)


Important point (sorry if someone else has made this!) - a green DC is not "the target", plant and livestock health is "the target".  The DC is an INDICATOR of CO2 levels, and in this case is most useful if moved around the tank to ensure that the colour remains consistent (indicating stable levels of CO2 round the tank).  For best plant growth the aim should be to run the CO2 as high as possible without your livestock showing signs of distress (gasping at the surface, fin clamping, decreased activity etc.).  As an example i run my CO2 VERY yellow!  My fish and shrimp are all fine with this though! THe important thing is that wherever i put my DC in my tank, it stays the same colour.  
If you have a spare powerhead i'd bring it into play - it'll really help everything!
Hope this helps,
Matt


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## AverageWhiteBloke (4 Jun 2010)

Thanks Matt I look forward to it, the dry left hand chamber is where I was aiming as well seems the best place to start. I have been keeping fish for over 25 years so probably like most people here I have one of them boxes in my house that has virtually everything you can think of   I could probably make a living off ebay but you can guarantee as soon as I sold something I'd wish I kept it but I do have lots of different elbows fittings etc.



> A valuable lesson!


One of many   
When I first had a crack at planted using Dennerle stuff years ago the opinion was slow turnover no more than 1 half times volume "plants don't live in raging torrents, look at a river the most plant growth is at bends or where the river slows the only thing that thrives in fast moving water is algae"(source Dennerle catalogue) an old book but I still read them they have the odd bit off useful information and very good individual plant descriptions and needs. That thinking has changed and so as mine, not only does the level of co2 need to be right, not necessarily the colour as you have mentioned but it also needs to made available to every plant in there to thrive. This is what I'm currently working on using a two pronged attack of increasing circulation using more pumps and stopping existing plants shadowing other plants from the flow.

All greatly appreciated  8) Coincidently the Dennerle book is my inspiration for planted, there are some pics in there that are out of this world and the reason my wallet is usually empty   Back then I would have bought everything I thought I needed regardless of the price but kids and being self employed means I have to strike a balance between two things I love.


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## Shadow (4 Jun 2010)

AverageWhiteBloke said:
			
		

> When I first had a crack at planted using Dennerle stuff years ago the opinion was slow turnover no more than 1 half times volume "plants don't live in raging torrents, look at a river the most plant growth is at bends or where the river slows the only thing that thrives in fast moving water is algae"(source Dennerle catalogue) an old book but I still read them they have the odd bit off useful information and very good individual plant descriptions and needs.



What if plant does not grow not because it cannot grow, but because they were carry by the current until it settle in the bends area?

In Aquarium we purposely plant them deep in soil or tie them in rock or wood, thus water flow will not be able to uproot them. Also we are talking about flow so fast until it look like washing machine  .


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## ghostsword (4 Jun 2010)

Many thanks for the article and for the explanation. 

The issue I have with BBA is that it only grows on the filter outlets and where current is strong, such on the koralias. 

It started to grow on some rocks, but not on plants, so I will take the rocks out and scrub them out. Will increase the CO2 and let it stay high, as the BBA took hold after the solenoid was installed.


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## AverageWhiteBloke (4 Jun 2010)

> What if plant does not grow not because it cannot grow, but because they were carry by the current until it settle in the bends area?



 Just highlighting how thinking has changed from about 10/15 years ago, I am beginning to understand how the exact opposite works thankfully.



> The issue I have with BBA is that it only grows on the filter outlets and where current is strong, such on the koralias.



My most effected areas are near faster moving water like outlets so the turbulence seems to have an effect on growth for BBA unless that's just you and me   Also it seems to take a while to develop its "beard" appearance so fast growing often trimmed plants seem ok as it doesn't have time to develop. Probably why it looks worse or rocks and the like or slower growing crypts that don't get trimmed much.


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## ghostsword (4 Jun 2010)

> Probably why it looks worse or rocks and the like or slower growing crypts that don't get trimmed much.



I get it on the rocks and on crypts., as I never trim them. 

Now I understand the CO2 fluctuation issue, and will do my best to ensure that remains stable, i.e. as high as possible.

I had CO2 24/7, but since installing the solenoid I have been shutting it down 1 hour before lights out. I will now change the shutdown to time of lights out, or 1 hour after, do not mind wasting CO2.

Also, I took out a lot of floating plants, such as Riccia, and that has for sure increased the water surface for CO2 to escape the tank.

The rocks are easy to clean, I will take them out and scrub them out, the filter outlets are something harder to sort out.


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## AverageWhiteBloke (4 Jun 2010)

> Also, I took out a lot of floating plants, such as Riccia, and that has for sure increased the water surface for CO2 to escape the tank.



I noticed the same thing with floaters, I generally leave a couple of small pieces the Guppy fry like hanging about in them and thin them out every couple of days. They make the tank look a little bit more natural.


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## ghostsword (4 Jun 2010)

I am replacing the floating plants with half emmersed MU on a hanging planter:





The shrimp hang around the planter and it is easy to trim.


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## Anonymous (4 Jun 2010)

http://www.skepticalaquarist.com/docs/a ... ocks.shtml here's a great article for you to read about safe rocks for aquarium  like gravel, rocks with calcium traces under lots of CO2 could mean a BBA disaster in your tank. I would keep away of petrified wood also, I still have headache after spending half a year wondering why I've got BBA, the flow was good, co2 was stable, nutrients were alright until I've read that Amano stopped using petrified wood 'cause it hardens the water .. darn, I had lots of them , had to reset the tank.


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## ceg4048 (4 Jun 2010)

clonitza said:
			
		

> ...rocks with calcium traces under lots of CO2 could mean a BBA disaster in your tank.


Hi,
   There is not been demonstrated any correlation between hard water and BBA. I routinely use water with high calcium content and yet have never suffered BBA as a result. Water that is high in Magnesium is a bonus for plants, and that's because the Chlorophyll molecule is a complex Carbon structure surrounding a Magnesium ion. Water that is poor in Mg  causes stunted growth specifically due to the inability of the plant to produce sufficient food due to poor chlorophyll density.

Along with it's role as a structural component in cell walls and in controlling enzymatic activity Calcium is a critical component in the enzyme responsible for splitting water and producing oxygen during photosynthesis. This mechanism is called the Oxygen Evolving Complex (OEC). Although there may be some level of Ca which is considered toxic, that level won't be found in any of our municipal water supplies. Soft water is much more damaging to plants than hard water, therefore associating hard water with BBA is a complete mis-correlation.

Cheers,


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## AverageWhiteBloke (5 Jun 2010)

The water out of my tap is very soft not even registering 1dgh on a test kit but I harden to 5dgh and 4dkh with water changes with JBL Aquadur  which is intended for re-mineralising RO water so I'm hoping the various salts that make up the overall hardness are in balance.

Unfortunately my tank evolved from a fish only system so other than a total strip out which isn't happening I'm stuck with the gravel I have. I will look further into substrates should I ever set up another tank though.

Neil


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## AverageWhiteBloke (19 Jun 2010)

Quick update.

Things seem to be improving slightly although I still use EC daily. As an experiment I did away with the reactor that was powered by the internal filter and just added the diy co2 to the air inlet pipe of the internal with excellent results, I was quite surprised. The sera internal came with a little spray bar and a couple of elbows so I pointed the bar vertical down one corner, the co2 sprays out tiny bubbles which are actually finer than comes out my glass diffuser   These drift about and cling to plants also I get the added benefit of a bit better circulation in that corner now the reactors removed.

I now have the pressurised glass diffuser in one corner and the diy internal in the other. I've even managed to get the BBA working in my favour, I positioned the diffuser under a heater where the control end is covered in BBA which I don't mind as it softens the edges and looks more natural. The tiny bubbles rise up and cling to the BBA holding them in the column for longer  8) That'll teach BBA to try and out wit me   

I'm getting better flow around the tank generally after some re-arranging of plants and a couple of good thinning out, I am still concerned about the flow though, after cleaning my glass and observing debris floating round the tank I can tell there is still a couple of dead spots or poor flow areas. 

Considering buying a Nano koralia for the back left corner to improve the situation but have a couple of quick questions, I see a few people saying that the new ones are better as the old ones were a bit noisy but which is the newer version? I notice that the grill from the pics I have seen are quite large openings and the impeller looks to be exposed and visible has anyone had and problems with shrimp investigating into there with antenna if that's the right word? 
Also my LFS guy reckons that in my 3x2x2foot approx tank that even a nano would be well over the top for a planted tank movement wise as I haven't seen one in action what do you think?

Finally the ones I have seen on you tube were probably bigger models but they do look a bit bulky the specs say 2 and 3/4 inch but not sure where they took this dimension.


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## AverageWhiteBloke (21 Jun 2010)

Ordered the 900 Evo from Cardiff aquatics only Â£18.99 plus delivery I found it linked in this board, seems the EVO replaces the older versions so are a bit smaller and quieter among other things.

I hope this can clear out my dead spots only time will tell, this is just a temp measure to make do with what I have at the moment. The lid on my Aqua-one has a few cracks in it and the clear perspex is quite yellowed which is Â£125 for new and the filtration system is not very plant friendly so I'm going to save up some pennies and go the whole hog, I'm going to get a new light unit so I'm open top again which I prefer and a decent canister with in-line co2.
It's my birthday soon so cash presents accepted this year


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