CO2 Fermenter for Fish Tank/Aquarium, from Carboy?!

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elwray

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Was debating posting this in the actual homebrew/Fermentation section, but figured it might not exactly be best suited for that area.

I have an aquarium with a good number of live plants that seem like they could use a little boost, so it was suggested I pump some CO2 into the tank with something like this:
DIY CO2 Fermentation

Well, it seems to me that I have a better source of CO2 in my carboys than some sugar water and supermarket yeast :D

Anyone have any input on how to accomplish this without compromising my fermenting beer? Assuming the beer is fermenting as it should and I have everything set up properly, a regular blowoff tube setup should be adequate to do this. Maybe add the checkvalve just to be extra sure.

Ideas?? Or am I just :drunk:
:p
 
I'd worry about pumping everything else into the aquarium that the yeast are throwing off--sulfur, etc... depending on the yeast and what they're eating.
 
I used to be really big into aquariums and this would work just fine except the only thing I would worry about would be a raelly strong fermentation and the karuasen goes up through the blowoff and into the fish tank.

You might want to set up a "holding tank" so to say. Take your blowoff tube and have that flow into a small bucket or other container about half way up the side. Then on the top have another tube coming out and going to the fish tank. That way the bucket would catch anything that would come from the fermenter.
 
Or you could always just use that as an excuse to start kegging and get a co2 setup :D
 
This works fine, but you have to meter the amount of CO2 that goes into the fish tank. I've got planted aquariums and inject CO2, and one of the small tanks has a "BIO CO2 reactor" which is a funny name for "fermenter". It's an actual commercial product that comes with a pack of sugar, some yeast, and then you add water. It provides about one month of CO2, and then peters out. I did the same DIY thing with soda bottles, but it's a pretty ghetto setup. Works all right for small tanks, but not for big ones. Still, some CO2 is better than none.

You have to be really careful about injecting too much CO2 into the water, as this will kill/asphixiate the fish. The best way to do this is:
SMS122 PH CONTROLLER+ Milwaukee CO2 REGULATOR MA957 - eBay (item 380148188021 end time Sep-10-09 05:33:51 PDT)

It is an electronic solenoid that dispenses an appropriate dose of CO2 based on your PH setting. As CO2 concentration goes up, PH level goes down. You set the low PH level so that it will shut off before killing your fish. Pretty sick setup, and definitely a great way to get lush and thick growth of plants in your aquarium.
 
the DIY CO2 method vs a CO2 cylinder is fine.
However...

the extra 'stuff' from the yeast will try to form a clear/white snot-like substance around the tube that enters the water. its not toxic, but u wnana keep it removed so it doesn' block the CO2 bubbles from being assimliated into the water.

option to fix this is to run the CO2 line into a small soda bottle full of water, then run a line off the top of the soda bottle into the fish tank. that way the water in the bottle 'scrubs' the gunk and yhou just get pure CO2 flowing up to the tank.

you DEFINITELY need a check valve so it doesn't suck fish water into the fermenter.

you CAN put too much CO2 in the water too, which could kill sensitive fish, especially pH sensitive fish. CO2 doesn't displace O2 from the water, but the pH will shock fish (hence the SMS122 PH controller by Milwaukee).

I never used that...i jus tgot my CO2 dialed in to a good 'bubbles per minute' that kept me at 35ppm of CO2. ran 24/7 because I have fairly hard, well buffered water so when the lights went out my CO2 only rose 4ppm over night.
 
I've got a keg setup so I could just pipe in bottled CO2, but where's the fun in that?! ;)

I don't have any fish in there at the moment, just plants. Might be worth a shot for the next beer, just to see what happens! I like the idea of the holding tank, I'll give that a shot if I end up doing this.

If I get good results I'll pick up one of those pH controllers, that's a really clever setup!

This would be an awesome way to combine two of my favorite hobbies, homebrew and aquariums! Now if I could just integrate motorcycles in there... :p

Thanks for the info, much appreciated!
 
I've got a keg setup so I could just pipe in bottled CO2, but where's the fun in that?! ;)

I don't have any fish in there at the moment, just plants. Might be worth a shot for the next beer, just to see what happens! I like the idea of the holding tank, I'll give that a shot if I end up doing this.

If I get good results I'll pick up one of those pH controllers, that's a really clever setup!

This would be an awesome way to combine two of my favorite hobbies, homebrew and aquariums! Now if I could just integrate motorcycles in there... :p

Thanks for the info, much appreciated!

If you have adequate lighting (>2 watts per gallon), you will see a vast improvement in your plant growth. Over the course of two weeks you'll likely go from nice neat planted aquarium to underwater jungle! It also depends on what kind of plants you have. Some plants like anubias actually like lower light, while some like cabomba, moneywort, and "grassy" plants like high light and high CO2. What kind of plants are in your tank now?
 
What were the results of this experiment?
I've got a 6 gallon batch of mead started and I hooked it up to my ladder diffuser, but somehow the CO2 isn't getting into the tank. I can't figure out what is going on.
I have airline tubing hooked up to an airlock, secured and made (what should be) airtight by several layers of duct tape. The air lock is bubbling, and it has no where to go but the tank but it seems to be disappearing...

I'd appreciate any Ideas for what I am missing :)
 
BTW I did get it working- it is pretty cool. I had tubing that fit relatively well into an airlock, then made a plug with aquarium sealant. Duct tape kept springing leaks.
 
BTW I did get it working- it is pretty cool. I had tubing that fit relatively well into an airlock, then made a plug with aquarium sealant. Duct tape kept springing leaks.

I was gonna say, had to be a leak. Gas will always find the path of least resistance. a pinhole leak in duct tape is less resistance than the water.

You have the information on measuring your pH and alkalinity (Kh) to determine CO2ppm in the aquarium water?

Don't go over 40ppm of CO2, and some fish will not tolerate it well (like german blue rams)
 
I do not have specific measurements, but I've installed a drop checker so that I will know if the CO2 goes too high.
I don't have any special fish in this tank- guppies, killies, bala sharks and ottocinclus
 
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