i kinda went to 3 of the largest DIY hardware stores in my place..
ace hardware, handyman, citi hardware..
they didn't have T5 high ouuput, they only had the common T5s and T8 flourescent tubes..
@Hopyy ; currently at my place, i have a few T5 fixture with a diffuser cover attached to the fixture, should i use it or remove it ?.. ( its a 1 or 2 mm thick translucent plastic with ribbed lines to spread the light..)
@wsharp ; its 100 gal, 4ft length, 2 ft width, 21inch depth..