Besides which, adding ammonia to a tank with fish? Not an obviously good idea.
Ammonia and ammonium exist in a pH controlled equilibrium; adding either will actually end up raising the toxic ammonia level by the same amount.Its ammonium, so its not gonna be very toxic, unless the pH is very alkaline, due to the conversion to Ammonia. But ammonium additions will actually bring on algea explosions, since ammonium takes a lot less energy to consume over nitrate.