How long cycling can take for a 10g aquarium? I already have 3 weeks and I seems to have problem to keep ammonia low. I have to make water changes 1 days , 1 day not. The day I don't do the water change the ammonia is at .50pmm , I don't know if my testing kit is bad but I always get 0 from nitrite and right now getting 40 from nitrate. Also don't know if is a bad thing but since I live in Puerto Rico the aquarium is around 85 and 89F . Although they seem happy.