I'm back with more questions. Still not completely clear to me. So surface agitation is fine to a point while running CO2, so long as we are not creating air bubbles, which degas the tank. I plan to run a powerhead, low power, to increase flow while running CO2. I'll make sure the powerhead is positioned much below surface and that I use a small sponge. I wont crank the powerhead enough to disturb too much. I should know the answer and I think I do but to clarify this seen as Im not yet at a stage where I can measure for myself, is this fine? Won't degas?