Once apon a time, my 55 gallon had DIY, CO2
. It used a bubble ladder and a diffusion bell, and had a HOB
filter. I would get 15-20 ppm
I was concerned over "losing" CO2
to my HOB
filter, and switched to 2x Fluval 303 cannister filters. This helped some, but my PPM
's did not go up too much. I deciced the real problem must be I needed a more efficient reactor. So i build one out of an old gravel vac, and put it on the outflow (i used a powerhead before i switched it to the outflow). It had a venturi loop too.
This is where I learned one major reason folks do not do this much (or for long). You have no control over the "flow rate" on DIY CO2
. If you add a highly efficient reactor, you can easily get too much CO2
here is an old post where I just set it up, and was getting 45ppm (with a powerhead)
Here is 2 month later, when I got real good at DIY CO2
, peaked at 130+ppm
and wiped out half my tank. I quickly went to pressurized. I lost enough $$$ in fish to justify the pressurized cost. Which turned out to be more reasonable than expected. ($40 2 dial welding regulator, $70 5lb cannister, and about $7 for the needle valve) (I filled the 5lb last month - so it lasted about 7 months, and was $7 to refill)
So bottom line, it can be done, it works well...maybe too well. And in the end, the lack of control on DIY CO2
makes it dangerous, once you get it working well.