Yes, another question ...
When starting a planted tank with a few fish. How much aeration do I
need? I want to minimize surface turbulence to keep the injected DIY
CO2 in the tank.

I am using a canister filter. When I make the spray bar move the water
without disturbing the surface I get bubbles and some living things
floating at the surface. When I move the surface around, the stuff seem
to disappear.