I started cycling my 100g with dead rock 3 weeks ago. I started off with adding ammonia until it was at 2 ppm and also added a bottle of micobacter start xlm. The ammonia reading right now is 0 ppm, nitrites are at 20ppm and nitrates are at 10ppm. Do I need to keep adding ammonia or should I wait until nitrites are at 0 and then do a water change and then add ammonia to check if both ammonia and nitrites go to 0 within 24hrs? Thanks!