How to get really good CO2 diffusion from a Powerhead

no prob but you already have most of what you need to convert the set up to a reactor. if you have an old siphon sitting around you may want to look at the diy reactor.
 
A Whisper 20, but I am about to upgrade to a Penguin 150 in a couple of days. But I have a concern that the Bio-Wheel will gas off alot of CO2.
 
I plan on upgrading to a 29 or 30 gallon tank in the next month or so, and the only canister filter I could find that is not too expensive for me is the Rapids Mini Canister Filter, and that only goes up to 20 gallons capacity.

Would a Penguin 150 gas off too much CO2 so that adding it to the tank would make it ineffective?
 
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