Wait a minute... you're saying that because both fish and chicken are dipped into the breading, someone allergic to seafood might get sick. Correct?
Well, that is the LEAST of your worries. Once raw chicken or seafood has come in contact with that breading, the leftover breading should be thrown away. There should NOT be a giant tub of breading that is being used all day long. NO, NO, NO! A small amount of breading should be taken from the tub, per order, and whatever is not used should be discarded.