The Planted Tank Forum banner

DIY co2 for 75 gallons

2186 Views 9 Replies 8 Participants Last post by  TekWarren
Hi everyone well I've been thinking about adding co2 to my tanks I have 2, 5 gallons fluval chi 2 , 2.5 gallons a 10 gallons and my 75 well for all the tanks I've been thinking on a DIY project using bottles but I've been reading that it won't work in my big tank but no one says why is it true? Isn't there any other options? Or should I just go for the regular way ( co2 gas tank celenoid and all that) ? Well I could use some advice thanks for reading :)
1 - 10 of 10 Posts
The problem is that the DIY CO2 production is not fast enough to produce the amount of CO2 you would need for a 75g tank. You could do it if you set up ~10 DIY CO2 bottles, but that would take up a ton of space and be a ton of work and much more expensive over time then just getting a pressurized system.
Well that makes sense So I guess I'll do the set up just for the small tanks
on a 75 u need like 10-15 2 litter bottles and then some way to diffuse it, i tried a few months on a 55, if bigger than 30 gal get a reg and go that way, way way cheaper in the long run also
I've been doing DIY CO2 (yeast bottles) on my 40 breeder for quite a while now. I get good pearling with 6 2 liter bottles. I have them tubed in pairs with check valves so I can change a pair each week without the whole system losing pressure. It works but, and only takes me a few minutes to change out the solutions but it still gets old sometimes lol.
I've been doing DIY CO2 (yeast bottles) on my 40 breeder for quite a while now. I get good pearling with 6 2 liter bottles. I have them tubed in pairs with check valves so I can change a pair each week without the whole system losing pressure. It works but, and only takes me a few minutes to change out the solutions but it still gets old sometimes lol.
Gets old, tell me about it, lol. I diy-ed my 55g back in the day for a couple of years. I only ran (4) 2L bottles and changed 2 of them every 12-15 days. I got great results for the plants I had. It became a chore and that's when I decided to go pressurized myself. Co2 needed depends alot on the plant selection. Don't over look this part as many do. I can't speak on why you can't diy a 75g for I haven't done it and I never heard that you can't. Typically you can diy anything. You may just have to do alot more maintenance than you wished for. Run them in pairs for sure but you may want to run them in quads for a 75g. Forget about 2L. Go 3L or even the 1 gallon fruit punch drinks you get at grocery stores. Use a cerges or rex griggs reactor on a lower powered pump/canister to make sure you get near 100% diffusion. Search around for the recipe that last alot longer than just yeast and sugar. I think its like champagne yeast or something like that. If you can save up, I would definitely go pressurized though. Less headache for sure and it won't be a choir. If your a very busy person, diy will consume alot of your time.

Typically diy is just to get your hands wet to get a feel for what co2 can do for your tank. That's why most do it on smaller tanks. The larger the tank the more co2 needed. For a 75g, you can can split the load for opposite sides of the tank and run two inlets of co2 instead of just combing all the co2 lines with only one entry to the tank. Power heads will help spread the love around the tank. The biggest downside to diy co2 is that it can't be regulated. What you get, is what you get.
See less See more
I have not tried this but many say once you get over a certain size tank, DIY will not work. I figure it will, just make two or three different rigs.

I would bet if you did 2 or 3 rigs with 2-3 bottles, you would actually get more consistent CO2 than a smaller tank. The major downside of this is if you stagger refilling each bottle, you may be refilling a bottle every other day or so. I do think it can work though.
If you mad enough - you can have a DIY CO2 system for any aquarium size. ;) I did grow out of the this - http://www.plantedtank.net/forums/showthread.php?t=45152&highlight= - system into pressurized set.
See less See more
3
I've been using a 5 gallon carboy to supply C02 to my 72g bowfront for a while now. It definitely can produce enough to supply for the tank. Still, there are problems: The C02 production is often too much in the beginning and too little at the end. You cant just shut off the valve if the flow rate is too high because the pressure will build out of control on the system and break a seal somewhere. This forces you to be constantly removing and replacing the diffuser in the tank to keep C02 at optimum levels. If you have a way to control the temperature of the brew, keeping it at a low 55 degrees will give you good control over C02 production. The lower them temp (don't kill the yeast) the slower the fermentation. Using temperature control, I can get a solid two weeks out of one batch without having to change anything.
See less See more
The problem with only using a large single container is that when it comes time to change the solution you cause a WILD swing in CO2 in the tank while it builds back up. This is why I went to a 6 2 liter bottle setup on my 40b. The bottles are tubed in pairs with one way valves I change one set each week...thats a 3 week run time and my output is steady and my system (the remaining bottles) do not lose pressure when I take a set offline. I've not run into temperatures. I keep my house at 68F in the winter and I only run AC when if it is so hot we can't sleep. The output is visually the same on my bubble counter. I have changed over to using whine yeast over the last month...plain old grocery store stuff was working great but my dad gave me the whine stuff to try. I keep wanting to see if it will run longer between changes but DIY is so fiddly I haven't had the nerve to experiment again with things working so well.
See less See more
1 - 10 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top