Bottled addatives should only be used if a respective test kit shows a defficiency. Other additives for general use essential elements should be replenished when you carry out a water change with a good salt...so, should not be a need for them.
Well just make sure your using a good brand of salt when doing water changes... The more expensive salts are better for your tank (essential elements) also in my FOWLR I dose with PURPLE UP It helps a little bit and hey it helps create the necessary levels for coraline algae growth so it looks good too lol.