Co2 For A Large Tank

[KPD]

Hi again
I'm new to CO2 injection and even planted tanks. I have a roughly 700 litre tank (720 litre but less with rocks, sand, etc) and I want to set up CO2 injection at about 15ppm. I always enjoy the challenge of keeping my expenditure down, and am happy to do a bit of DIY.

One way I was thinking of to get the necessary amount of CO2 into my tank was by direct injection into the impellor of a powerhead. I have a load of 1000lph powerheads laying about from my reefkeeping days, and I was wondering if anyone here had tried direct injection into a pump impellor. Do you think the resutling bubbles going into this volume of flow would be fine enough and in suspension long enough to disolve?

Sorry if this is a dumb way of doing it...or if its an old chestnut that I shoudl have found in serches .

Cheers for any help
Kev

 

[garuf]

Hi again
I'm new to CO2 injection and even planted tanks. I have a roughly 700 litre tank (720 litre but less with rocks, sand, etc) and I want to set up CO2 injection at about 15ppm. I always enjoy the challenge of keeping my expenditure down, and am happy to do a bit of DIY.

One way I was thinking of to get the necessary amount of CO2 into my tank was by direct injection into the impellor of a powerhead. I have a load of 1000lph powerheads laying about from my reefkeeping days, and I was wondering if anyone here had tried direct injection into a pump impellor. Do you think the resutling bubbles going into this volume of flow would be fine enough and in suspension long enough to disolve?

Sorry if this is a dumb way of doing it...or if its an old chestnut that I shoudl have found in serches .

Cheers for any help
Kev

reef keeper you say, needle point powerheads are IDEAL for co2 injection.
give us a minute and I'll post up tom barr's guide.
If not mazzai injectors are the way forward

 

[KPD]

reef keeper you say, needle point powerheads are IDEAL for co2 injection.
give us a minute and I'll post up tom barr's guide.
If not mazzai injectors are the way forward

Not sure about the needle point powerhead....is this the sort with the special impellor used in protein skimmers? I have one of these on the Deltec skimmer which is still out in the garage, but would prefer not to use it on the tank. The general powerheads I have are the standard 1000 litre per hour and 1400 litre per hour sort that can also be used to drive venturis or undergravel filters.
I'll have to consult google on what a mazzai injector is
Kev

 

[garuf]

Those are the ones.
http/www.barrreport.com/co2-aquatic-plan...powerheads.html

For a tank your size you'd need a multiple of diffusers or a reactor, but then I'm not sure there are any good ones about.

 

[KPD]

Those are the ones.
[URL="http/www.barrreport.com/co2-aquatic-plan...powerheads.html"]http/www.barrreport.com/co2-aquatic-plan...powerheads.html[/URL]

For a tank your size you'd need a multiple of diffusers or a reactor, but then I'm not sure there are any good ones about.

Hmmm...not keen on multiple diffusors. They seem a bit invasive and labour intensive. Also, being a real miser, I'm not keen in investing in a new pin-wheel pump. I might look at DIYing a pin-wheel of sorts for the powerheads I have though

Another possiblity that occurs...I have a bunch of old canister filters out in the garage. I was trying to avoid having to run more plumbing tubes in to the undercabinet....but if it can't be avoided then maybe I could put a powerhead of two into the canister of a canister filter and use this as an kind of active reaction chamber? Not keen on having to plumb in more pipes though. I might try playing with some kind of loop on the powerhead before going the canister route.

What do others use on large tanks?
Kev

 

[newfyman]

Look at the DIY reactor on Tom Barrs site some interesting reading on dissolving Co2 and looks a very good reactor too

 

[fozziebear]

i have mainly seen reactors used on large tanks, that or a large ceramic diffuser at each end, with the bubbles being blown around by the filter output.

 

[KPD]

Just thought I'd add that I've had a go at DIYing a direct CO2 feed into the back of a pwoerhead and it works a treat. Drop-tester has slowly gone from blue to green over a few days and is steady. Teh output is puffs of very fine bubble that instantly get blown around the tank. I'll tyr and get a picture tonight to post. The only drawback is that there is a puffing sound each time a bubble gets drawn in. I may have a go at modifying the setup to see if I can get around this.
Kev

 

[garuf]

Just thought I'd add that I've had a go at DIYing a direct CO2 feed into the back of a pwoerhead and it works a treat. Drop-tester has slowly gone from blue to green over a few days and is steady. Teh output is puffs of very fine bubble that instantly get blown around the tank. I'll tyr and get a picture tonight to post. The only drawback is that there is a puffing sound each time a bubble gets drawn in. I may have a go at modifying the setup to see if I can get around this.
Kev

DIY it into a needle wheel supercoley will back me up in saying its worth it. They become much quieter once driller out too.