I need more information on your tank.
1) how big is your tank?
2) what lightning you using?
3) do you add plant fertilizer that contains phosphate or nitrate?
80 g, Eheim Pro II w Hagen Surface Skimmer, TetraTec IN-1000, JBL Aquabasis and Sand subtrate,
1st 40w Lighting: 40W Marine Glo
2nd 80w Lighting: 2 40W Power Glo
3rd 80w Lighting: 2 40W Aqua Glo
Whole set of Azoo fertilizers
3.8 kg Pressurized co2 tank