Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
While some root tabs may have some ammonia in them, it is not of sufficient quantity overall to produce any dangerous ammonia toxicity levels in most tanks, even if it were to leach right into the water. I've used 2 or 3 different types of root tabs over many years in my planted discus tanks (discus being very sensitive to any level of ammonia), and have never experienced any ammonia test reading from root tabs.
A tank's beneficial bacteria would deal with any such ammonia produced, just as it does with other sources of ammonia production within a tank.