Yes, check for water quality readings more often. But, I've had a QT up and running now for almost 2 mos, 20L, with 3 fish in it--one a hippo tang with HLLE. It has powerhead, Fluval canister and some bleached coral heads I took from my old FO tank. Have not gotten any ammonia, nitrites, or cycling. While the tank was seeded by the old dead rocks I took from the other tank, I did not use old tank water, just distilled water.