# [Wet Thumb Forum]-Cannister as CO2 reactor



## imported_molahs4 (Feb 3, 2003)

My CO2 goes directly into the input to my Eheim 2217. It took 24 hours to start dissolving the CO2 into the water but now it seems to be working just fine as a CO2 reactor. I read something that said this is a bad idea. What could possibly go wrong?


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## imported_molahs4 (Feb 3, 2003)

My CO2 goes directly into the input to my Eheim 2217. It took 24 hours to start dissolving the CO2 into the water but now it seems to be working just fine as a CO2 reactor. I read something that said this is a bad idea. What could possibly go wrong?


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## GulfCoastAquarian (Feb 3, 2003)

The only risk, mechanically, is that the CO2 will collect in the impeller chamber and cause the pump to airlock. This causes the filter to cease pumping and can kill the biological filter.

That said, Eheims are pretty resistant to airlock (unlike my Fluval) so as long as you're not inundating it with more than 1 bubble per second, it should be fine.

-Sam P, BSME
My Website


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## gsmollin (Feb 3, 2003)

It can also ruin the pump. This has happened.


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## chbak014 (Feb 3, 2003)

heheh, i wish i had a canister filter too, but yeah, well, what i did was just connect my co2 to my hagen ladder diffuser. heheh. it works fine, as long as there isn't much surface agitation. 
-charley

http://www.geocities.com/charleybak/aquarium.index.html


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## deltaboy (Feb 14, 2003)

> quote:
> 
> Originally posted by chbak014:
> heheh, i wish i had a canister filter too, but yeah, well, what i did was just connect my co2 to my hagen ladder diffuser. heheh. it works fine, as long as there isn't much surface agitation.
> ...


http://www.geocities.com/charleybak/aquarium.index.html
[/QUOTE]

can you explain that? How'd u set that up??


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## IUnknown (Feb 24, 2004)

I've run my Co2 through my eheim 2224 for about a year, no problems, rotor can be replaced fairly inexpensively (I think) if it is a problem. What do you mean 24 hours to start dissolving Co2? Doesn't it happen right away?


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## imported_aspen (Feb 20, 2003)

i also use a hagen ladder diffuser, and i like it. a bubble is released at the bottom, and it zig zags back and forth slowly up the ladder. the bubble shrinks as it rises slowly. i point my filter at the ladder 2/3's from the top. usually the co2 bubble totally dissolves, rather than running out the top.

i run 10- 15 ppm in my 35, with 1 bubble every 6 seconds or so from diy. i could speed up the reactor (more yeast), but this is adequete. you can also count the bubbles, which is nice. i use 1/8 tsp all purpose yeast, 2 cups of sugar 1.5 litres of water. runs for 4 weeks. i change it before it slows down though.

rick


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## deltaboy (Feb 14, 2003)

I'm so confused here it's scary!







I'm assuming ur using the hagen reactor along with the bouble difuser. If that is the case, am I to conclude u make your own mixture of yeast and sugar and bypass the activator and stablizer mix that hagen sells/provides?


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## JaredW (Feb 2, 2003)

I suspect that in some cases O2 as well as CO2 gets knocked out of solution and collects to form a gas lock.

Jared

Plant Resource Page and photos


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## anonapersona (Mar 11, 2004)

deltaboy, the Hagen reactor only holds about 2 1/2 cups volume, so to get the volume aspen mentions one must use a 2 liter bottle for the generator instead of the Hagen reactor.


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## deltaboy (Feb 14, 2003)

> quote:
> 
> Originally posted by anonapersona:
> deltaboy, the Hagen reactor only holds about 2 1/2 cups volume, so to get the volume aspen mentions one must use a 2 liter bottle for the generator instead of the Hagen reactor.


wait the terminolgy is killing me. lets define it. The Generator is the bottle/yeast/sugar combination. The reactor is the zig zag or equivilant device which disolves the co2 in water? If this is the case u mean I should use a standard 2 liter bottle as a generater but keep it connected to the hagen reactor. Right?


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## gsmollin (Feb 3, 2003)

> quote:
> 
> Originally posted by IUnknown:
> I've run my Co2 through my eheim 2224 for about a year, no problems, rotor can be replaced fairly inexpensively (I think) if it is a problem. What do you mean 24 hours to start dissolving Co2? Doesn't it happen right away?


The "24 hours" is the latency between any changes to the CO2 injection, and a new steady state concentration in the aquarium. The CO2 does dissolve immediately, but about a day, or two, are required before the aquarium reaches a new equilibrium concentration.


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## Steve Hampton (Feb 13, 2004)

> quote:
> 
> Originally posted by JaredW:
> I suspect that in some cases O2 as well as CO2 gets knocked out of solution and collects to form a gas lock.
> ...


http://www.brainyday.com/jared/aquarium/
[/QUOTE]

Yes, I agree completely with you on this point Jared. I use a Magnum 350 as a reactor and while the impeller isn't likely to get an air lock because of it's location it does however have O2 build up and cause a gurgling sound during the day. During the night the O2 dissolves and the sound stops until the next day a few hours after lights come on. I inject CO2 24/7 so it's not the CO2 that's building up in the canister. Actually, I think John Wheeler was the first to mention this about his Magnum? Anyway, whether the air lock is from CO2 or O2 is sort of moot. The canister's with the impeller located on the top are quite likely to develop this problem at high levels of O2 and CO2.

One other point, I've noticed that the rubber seals do deteriorate much quicker when exposed to CO2, though I'd suspect this would be the same whether I was using the Magnum as just a filter or it's combined used as filter/reactor.


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