Planted Tank Guru
Join Date: Nov 2009
Location: Missouri united states
Lot's of folk's use fertilizer's and lot's of em (daily with EI dosing), +fish food's,fish waste, and don't get algae.
8 watt's of t5 over roughly two gal is maybe a bit much, but could be bout right depending on how long the light is on ,or how high over the tank the light is.
Seachem's flourish comprehensive is largely water,and micro nutrient's with not much in the way of macro nutrient's (a little).
T5 bulb's NO or HO are still considerably more light than T8 bulb's.
2 gal tank ain't very deep and the light is often more than what folk's think they need.
Organic waste in the way of fish waste,fish food's,poor maint, are more likely to precipitate algae bloom than adding fertilizer unless WAYYYY overdosed and even then,,what may be too much?