You mean the ready build led light set or the individual led by itself?
Depending on your tank height, you can space your led so that it can cover the whole
tank volume evenly (For DIY only)
All LEDs for flourescent tube replacement, whether T10,12 8 or 5 are make from 1/4 watt to 1 watt led.
Of course can light up any tank but can your life stock survive and grow over long period of time ?