well i am no scientist, but i can't see how either would be affected by a little salt--we are not talking brackish, but just slightly salted...nitrate is the end product of the nitrogen cycle , and from personal experience, i have not had a problem with even high levels of aquarium salt such as when treating disease harming my bacterial colonies....and the salt wouldn't break down to anything but sodium and chloride, and that shouldn't have anything to do with ammonia levels...ammonia is nitrogen and hydrogen...hope this helps, can only tell you my experience and what i have read but there may be other opinions out there....