you will need to dose the tank with prime every other day and do water changes every other day till ammonia reads 0, and nitrite reads 0 and showing nitrates. ammonia bad, nitrites worse, single dose of prime will handle up to 2 ppm of both ammonia and nitrite, the reason for every other day is prime lasts up to 48 hours, after that it releases the bind back into the water, prime does not remove but binds making it inert until it wares out. can dose up to 5 times recommended dosage but has a diminishing return, max dose will handle 4ppm. I would stick with single, do the water changes and test the tank cycle kicks back in.