I am relatively new to the whole fish keeping hooby. i have a 20L fresh water that i am finishing. i also have a 5 gal that was for a goldfish but it died. i was wondering if a 5 gal could be used to make a saltwater aquarium, and if so how difficult would it be to set up. i mainly want a clown fish or two if possible, no reefs or inverts. would this work with a clown? if not any other fish?
Possible? Yes. But--small SW tanks are a lot mroe work to keep stable and healthy than a larger setup. Evaporation from just one or two days can raise salinity to lethal levels, so they require daily attention. I do not recommend anything smaller than a 30 for a first SW tank.