the main question... why do you want a sump for a tropical tank?
basic setup for you would require the following:
-Some sort of overflow setup to get water from tank to sump (you can buy hang on back syphon overflows, which I dont recommend because if you lose syphon and your return pump is still going your tank will overflow) Or, you can drill the back of the tank, a company called glass-holes sells overflow kits that include drill piece to cut tank, the overflow box, and other misc. pieces needed.
-A return pump to get water back up to the tank. The size of the pump will depend on the gph that the overflow is moving from the tank down to the sump. again, most companaies specify on the overflow setup (whther it be a drilled kit from glass-holes, or a hang on back kit from say Eshopps for example)
-Tubing for overflow and return, whether it be PVC or just regular flexible tubing
- Sump of your choice.. when I built a sump tank setup for my reef tank i used to have, i purchased a aquarium and just split it up with different sections (skimmer section, which you won't need.. a refugium with macro algaes and then a return section for the return pump). you want to make sure you test the tank first to make sure you won't have an overflow issue when you cut the power to the return pump or incase you lose power and it shuts off, the tank will drain until it the water is at the level in which the overflow is at.