Question About Defusing CO2

**Cliff** · 02-27-2013, 01:10 AM

I am getting ready to set-up my first pressurized CO2 system on my 90 gallon and I am trying to decide the best approach to properly defusing the CO2 into the tank water

I have been reading about how some hobbyist have the CO2 injected directly into the intake of a canister filter. In theory it sounds like a good idea as more of the CO2 can get dissolved into the water while the water flows through the filter. From what I have read, the pH would have a larger impact on the bacteria in the filter than the extra CO2 in the water, so in threory, it could work as long as I did not allow the pH to drop

Just wondering is anyone here has ever tried this and if it resulted in a loud filter or trapped air/CO2 around the impeller

**KingFisher** · 02-27-2013, 01:16 AM

The problem with that method is that the water flowing from the filter comes out at or near the top of the water level in the tank, and therefore most of it offgasses before it has a chance to circulate in the tank. When you use a reactor, you place it 2/3 of the way down from te top of the tank so it stays in the water longer. I have also read that the CO2 is bad for the rubber seals and impellor of your filter.

**Cliff** · 02-27-2013, 01:20 AM

I never read about the effects on the seals

Thanks Kingfisher

Sounds like it would be best just to get a traditional defuser

**KingFisher** · 02-27-2013, 01:23 AM

A reactor is much more efficient and you can easily make one DIY if you want. All you need is a powerhead and a water bottle.

**Cliff** · 02-27-2013, 01:31 AM

I will look into that as well

Thanks Kingfisher

**Cliff** · 02-27-2013, 01:46 AM

I think I might something like the either of the two below ones. Seam easie enough and I could use the maxijet 1200 powerhead that I already have in my spares closet. Seam like it could also be easy enough to keep out of site behind a large pc of drift wood

WARNING: you may want to turn down the volumn on your PC before watching this below video

**Aeonflame** · 02-27-2013, 02:06 AM

I made one with a different design.

**Cliff** · 02-27-2013, 02:43 AM

Nice vedio Aeonflame, thanks for posting it. That looks easy enough for me to build

**Aeonflame** · 02-27-2013, 03:07 AM

It works well because a jet of water is shot through the Co2 and then swirls around the inside of the bottle. This increases the surface area of water being exposed to the gas before it is returned to the tank.