[frozenbarb]

some guy on another forum said Using co2 wont kill algae, but instead it makes it grown more, as the algae feeds on the co2


and about water agitation, if there is high water agitation will there be higher amounts of co2 or less

 

[epicfish]

Algae uses CO2 just like plants do. As you bump up your CO2, both your algae and plants will grow. HOWEVER, your plants will grow much much faster and suck up much of the nutrients in the water column. With this lack of nutrients, algae will be outcompeted by your plants and so you'll have less algae.

It's the acceleration of plant growth that kills the algae, not the CO2.

Higher surface agitation leads to increased outgassing of CO2 from the water and less CO2 in your tank.