Easy & Somewhat effective CO2 diffusion method?
So my Hagen Elite Mini broke today, and I don't have anything to diffuse my DIY CO2 with. My tank is only 7.5 Gallons, so any type of powerhead will be too big or will overcirculate the tank. Right now I'm feeding the CO2 line into the intake tube of my HOB filter, which I know isn't very efficient, but it's only temporary, and that's all I have right now. So, what's the best way to diffuse CO2 that takes up the least amount of space and when you're short on supplies? If I have to purchase something, I'd like it to be $20 maximum. Thanks guys.