When to Add Nitrifying Bacteria?

Adding the nitrifying bacteria at the beginning gives them the best chance for success because they are not inhibited by high concentrations of ammonia or nitrite.

When should I add bacteria to my aquarium?

You need to add bacteria to an aquarium as often as you add new fish to the tank or change its water. If you change your aquarium's water once every two weeks, then you need to add bacteria to your tank two times a month. This ensures the bacteria can keep up with the waste conversion.

Can you add too much nitrifying bacteria?

You can't add too much good bacteria to a fish tank. The beneficial bacteria will feed on the amount of ammonia available for it. If there are more bacteria than food, the extra bacteria will die or become dormant. A more common problem is not having enough nitrifying bacteria.