I do exactly that...and its quite easy to do
...hook up a cheap air pump on a separate airline tube and check valve and inject it into my reactor right before lights out (because plants are not converting CO2 at night)...it mists the tank and the bubble is gone by the morning
my fish used to gasp at the surface in the mornings -they stopped doing that but personally I think they were just being dramatic because when the lights turned on, they would swim mid tank with no problems after less than 10mins
since then, Ive given away my fish and started my tank over...but will probably reconnect it after my tank has established and cycled
Simple surface agitation should have fixed that
plants don't absorb that much oxygen, nor do they release that much co2..