[mr.schertz]

Wanting to go with a small power head as my diffusor for my co2. Whats the smallest powerhead that I can get for my 10 gallon tank that will still take an airline tube?

 

[Hoppy]

The powerhead doesn't "take and airline tube". You need to find a way to poke it into the inlet area of the powerhead, so the bubbles get immediately sucked into the rotor and chopped up. I have used the smallest powerhead I could find at the LFS, a "mini jet" as I recall, and I have also used a Maxijet 600. Both worked fine in that job.

If you do a needlewheel type mod to the powerhead rotor it works best. I just used a hot needle to poke holes in the rotor paddles, but there are more sophisticated mods that probably work better. I think all of the powerheads I still have have the holes in the paddles. One type that I don't think will work well is the Koralia type.

 

[Ichthyologuest]

I use a mini Hagen elite as a co2 diffuser as described in this article and it works surprisingly well. It wont push water around as much as a powerhead, but it will make a much better co2 diffuser than a powerhead and provide some water movement.

http://bit.ly/flAXHg

 

[iKine]

I used one of those hagen mini elite also, got it for $6 on clearance. It has a spot to connect an airline to, so just pump your co2 right to it.

 

[jstehman]

+1 on the Hagen Mini Elite. I'm using one as a diffusor on my 20g on the mid-setting for flow.