Preventing reflection from aquarium base..

I would think a matte black would work best to reduce the amount of reflected light, but the glass would still have a reflection.

Matte black or blue is probably your best bet, I will help to cut down on the reflection but won't eliminate it

i have a bare bottom tank on a black file cabinet. the file cabinet is not entirely matte but it makes no difference. theres still a reflection. but this is kind of cool cause the tank is downstairs and if i look from the upstairs, it reflects the fish from an angle i might not be albe to see them normally. (does that make sense?)