Co2 injection in large tanks

Zeus.

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if nothing else to understand more about the impact of pressure in the reactor that Zeus also pointed out.

I run my reactors at a low pressure compared to what foxfish did esp with having a bypass fitted to keep flow optimal in the tank, the flow I can have in the reactors can be very low with the bypass fully open and yet i still get fast 1.5pH drops but at a high CO2 injection rate
upload_2017-12-16_17-50-27-png.png


I have recently fitted Maxspect Gyres for tank flow/turnover is well taken care off. I have tried running the reactors at higher pressures/flow rates but they become too noisy and no net gain in the test I have done so far.

Filter flow rate isnt that important IMO is it doesnt increase the biological filtration rate it will pull more water though so will help remove more particles so mechanical filtration will be faster, but if you can keep the turnover higher in the tank by other means the particles will remain suspended in the water longer and the mechanical filtration will happen. As @ceg4048 points out to us the largest biological filters in our planted tanks are the plants esp the plant roots. Flow/Tankturnover is 'KING' in the planted tank for which we mainly use filter output to get, the advise is X10 output per liter of tank water, but we can also use powerheads etc to get the flow/output then the filter output is less a critical factor. We have also discussed the tanks at Green Aqua on the forums - stunning tanks Very high light yet relatively low flow/turnover rates, I have been to Green Aqua and they are stunning with relatively low flow rates
 

Zygorf72

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I run my reactors at a low pressure compared to what foxfish did esp with having a bypass fitted to keep flow optimal in the tank, the flow I can have in the reactors can be very low with the bypass fully open and yet i still get fast 1.5pH drops but at a high CO2 injection rate

Out of curiosity - what sort filter material do you use in the APS reactors? I didn´t seem to be described in the thread concerning your tank. At least I couldn´t find it.
 

Zygorf72

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Bioballs some details-
Co2 reactors setup and detritus build up


Plus working on
CO2 APS EF2 reactor with internal Venturi fitted - testing ATM

But have found little difference in pH drop speed or stable [CO2] if I use the boiballs or not :rolleyes: but work in progress on and off (Off ATM)

Interesting idea with the Venturi - I'll definitely be following that thread.

The Aqua Medic runs a bit differently than your setup, in the sense that it doesn't use a diffuser before the reactor. It simply bubbles co2 directly into the reactor chamber, without diffusing it. I think my approach for now will be this: I'll try substituting the ceramic rings for large bio balls (the ones that the reactor originally came with). This should hopefully eliminate the problem of smaller bubbles moving down the column of bio rings in the reactor and entering the outflow of the reactor. The question is, whether it will reduce the absorption rate of the reactor. It seems already to be running at the edge of its capacity. If it isn't capable of dissolving co2 to the required level, i guess the next thing would be to introduce a larger reactor chamber. The APS EF2's seem like a nice and fairly priced solution. Would like to get a see-through model though. I find it nice being able to see into the chamber, allowing one to actually see the waterflow and dynamics of the co2-gas within the chamber.

Although I do see the benefits of having the reactor on the outflow-side of the filter, I would like to avoid impairing the flow-rate. The Oase Biomaster really doesn't handle that well (otherwise it is the canister I've tried, I currently like the best). I dont mind cleaning the reactor chamber once in a while, if that is the main drawback. If and how much impact it will have on absorption rate, having it on the low-pressure side of the filter - I don't know. I'm currently running my canister on reduced flow, to avoid too much CO2 to enter it. It doesn't seem to impact the absorption rate significantly. I sounds like you have similar observations, using low flow in you reactor. Il try it out and see where it gets me. If that doesn't solve it, I guess I could look into closed loops or separate circulation pumps. I would like to avoid that starting off, since it will mean further investments and potentially more pumps humming in my living room.

With regard to flow rate - there seems to be a lot of different opinions on what the target turnover rate should be. I'm aiming for 6 times pr hour currently, which I've seen some people advocate. The reason for this, is that i have Angelfish in my tank - and they don't like to strong flow. The current flow-level of the tank is ok for them. 10x flow would almost certainly leave them being blown around the aquarium ;)
 

Zygorf72

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FYI i took the liberty of asking Green Aqua. They have set it up on 800 liter installations, so in their experience it should be able to drive a tank my size (530 liters). They do point out, that one needs good circulation of the water from the reactor, in order to ensure proper disperson of the co2 in the aquarium water column.
 

Zeus.

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i took the liberty of asking Green Aqua

:thumbup:

They do point out, that one needs good circulation of the water from the reactor, in order to ensure proper disperson of the co2 in the aquarium water column

which I would agree with in the sense good flow/turnover in the tank. As IME I can have low flow though my reactors and yet I can still get a 1.5pH drop in 30mins, so i cant see why high flow though the reactors is a requirement. Yes I do have a unique CO2 injection method with pH controler and PLC which I use to its full advantage and have different CO2 injection rates from CO2 on till max lights till CO2 off but I do have a fast pH drop then a steady pH from lights on till CO2 off. But most only have single steady CO2 injection which works also.

I do have the bypass on my reactors but most folk dont have. Increase working pressure in the reactor will/should help but not a requirement IMO/IME. most of Green Aquas reactors are high in the cabinet ( Had I good look when I visited) mine are on the base of my cabinet so maybe that helps too for me with lower flow but if higher better flow though the reactor is needed :rolleyes:. High flow though my reactors makes them very noisy and I end up with CO2 bubbles in tank so its a no no for me.

Every ones experience/opinion is different with CO2 injection and I have yet to find anyone who has a decent set of results/test/experiments to what works best and reasons to back it up, which isnt surprising as there are so many variables in our tanks
 

Zygorf72

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FYI i took the liberty of asking Green Aqua. They have set it up on 800 liter installations, so in their experience it should be able to drive a tank my size (530 liters). They do point out, that one needs good circulation of the water from the reactor, in order to ensure proper disperson of the co2 in the aquarium water column.

A little additional info from Green Aqua. They recommend a flowrate of around 900 l/h in the Aqua Medic reactor in order to achieve the best efficiency. They also recommend having the reactor on the outflow side of the driving pump or filter. Didn't say why. Just thought I'd add this to the discussion, so that others may benefit from Green Aquas response also ;)
 

Zygorf72

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...and I have yet to find anyone who has a decent set of results/test/experiments to what works best and reasons to back it up, which isnt surprising as there are so many variables in our tanks

Doesn't that apply to just about anything concerning planted aquariums? ;)
 

Zygorf72

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Ok. So I swapped the ceramic rings in the reactor out for the original bioballs for the reactor. While I was at it, I switched the tubing out, so that the reactor now is mounted after the filter, rather than before. Switching back to the bioballs made a massive difference. The flow of the filter was radically improved - also even though the reactor was mounted after the filter, rather than before. I would guess that the reactor, after switching back to the bioballs, reduces the flowrate of 10-20%, which to me is acceptable. The absorbtion rate of the reactor is all of a sudden massively improved also. It seems to me that this can be attributed to either of two factors. Sufficient flow (around 1000 l/hour) and/or higher pressure in the reactor, due to it being mounted after the filter, rather than before (at 1200 l/hour the filter actually creates a siginificant underpressure on the intake side). At a flowrate of 1000 l/h I had trouble, that the CO2 from outlet of the reactor was sucked directly into the outflow, rather than stay in the reactor. By standard the CO2 is bubbled out by a tube near the outlet of the reactor. Removing the tube, so that the CO2 bubbles out in the top of the reactor instead, completely remedied this issue.

I originaly swapped out the bioballs due to people on forums advocating that Eheim Mix (rough mechanical filter material) or ceramic rings would improve absorbtion rates. I've tried both and my conclusions are these. At flowrates of 1000 l/h Eheim Mix is inefficient, as the waterjet of the filter, simply sprays right through the material in the reactor. Ceramic media on the contrary reduces and restricts the waterflow so much, that the reactor (and the filter) becomes inefficient. It also has the negative effect of creating smaller co2 bubbles that reach the output side of the reactor, either escaping in to the filter or out in the aquarium itself - depending on whether the reactor is mounted before or after the filter.

To sum it up - here's my advice on the Aqua Medic 1000 reactor, based on my own observations:
- The Aqua Medic 1000 reactor is more than capable of supplying a 530 liter planted tank, when setup right.
- Mount the reactor after your filter or pump - it seems to increase the absorbtion efficiency of the reactor due the increased pressure in the reactor.
- Make sure that you have a flow around 1000 l/h in the reactor. This rate of flow seems to make it highly efficient.
- If you have trouble that the CO2 is sucked out of the bottom of the reactor, rather than bubble up into the reactor itself - remove the tubing inside the reactor, so that the CO2 bubbles out in the top of the reactor, rather than the bottom. This remedies the problem and does not seem to impact the efficiency of the reactor in any significant way.
- Do not swap the bioballs in the reactor for other media types. The bioballs are very efficient, when the reactor is set up right.
- The only flipside of the bioballs, is that it makes the reactor have the sound of running water. When it is behind closed doors in my aquarium cabinet, It is not loud enough to be bothersome to me. It might be to others though. Personal taste i guess.

I hope this can be useful for other owners of the Aqua Medic 1000 reactor.

Cheers
 
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Costa

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To sum it up - here's my advice on the Aqua Medic 1000 reactor, based on my own observations:
- The Aqua Medic 1000 reactor is more than capable of supplying a 530 liter planted tank, when setup right.
- Mount the reactor after your filter or pump - it seems to increase the absorbtion efficiency of the reactor due the increased pressure in the reactor.
- Make sure that you have a flow around 1000 l/h in the reactor. This rate of flow seems to make it highly efficient.
- If you have trouble that the CO2 is sucked out of the bottom of the reactor, rather than bubble up into the reactor itself - remove the tubing inside the reactor, so that the CO2 bubbles out in the top of the reactor, rather than the bottom. This remedies the problem and does not seem to impact the efficiency of the reactor in any significant way.
- Do not swap the bioballs in the reactor for other media types. The bioballs are very efficient, when the reactor is set up right.
- The only flipside of the bioballs, is that it makes the reactor have the sound of running water. When it is behind closed doors in my aquarium cabinet, It is not loud enough to be bothersome to me. It might be to others though. Personal taste i guess.

I hope this can be useful for other owners of the Aqua Medic 1000 reactor.

Thank you so much for this, very useful.

The only other problem that I see with this reactor is the tube size. For a 200-400gal tank, 12/16 tube is a very small diameter, which means that a bypass must be installed off the main pump/canister tubing, and that makes hitting the sweet spot of 1000lph even harder.
 

Daveslaney

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Yes this is the problem with regards to flow. But as most off the shelf reactors seem to be in 12/16 pipework size. Maybe the smaller pipe is for increased pressure in the reactor to aid co2 desolving rates?
So even thought the flowrate/ turnover through the reactor is less you will actually get more co2 dissolved into the water due to the higher pressure/ better desolving rate?
 
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Zygorf72

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Thank you so much for this, very useful.

The only other problem that I see with this reactor is the tube size. For a 200-400gal tank, 12/16 tube is a very small diameter, which means that a bypass must be installed off the main pump/canister tubing, and that makes hitting the sweet spot of 1000lph even harder.
You're welcome :)

Funny. My Aqua Medic 1000 reactor actually supports 16/22 hoses. It used to have an adapter that supported both 12/16 and 16/22. I sawed off the section with 12/16 barbs, and drilled the entry hole bigger. They must have changed the design, since I bought mine (it's really old ;)

I would agree that 12/16 is a a little small, when going for a flowrate of 1000 l/h....
 

Zygorf72

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This looks like the one Zeus uses in his setup described further up this thread. I contacted pond solutions, who are the sellers of this prefilter. It's not actually transparent irl. The picture is to examplify the filter material inside. The actual model is non transparent, like the ones on Zeus pictures.

Sendt fra min Nokia 7 plus med Tapatalk
 

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