with live sand and live rock ive done it in 3 weeks ive got 3 small tanks 5 gallon on deskin office. withone small fish in it. 25 gallon reef in office standing...30 gallon at home..live rock live sand and a clown fish help the cycle.. dont put damsels in u will never get them out and rip your tank apart i nprocess!!!!!!!unless u like damsels of course lolol they pretty but too aggressive. crab shrimp nippers and not nice!