Am leaving for 4-5 week vacation and don't know how to prep spa. We don't have anyone to maintain it while we are gone. We are going to dump and refill as soon as we get back (because cya is at 150!...learned cya lesson the hard way. Pool store never told me about cya, but that's another story). I really don't want to come back to a pond. Spa sales guy suggested putting two @ease chlorine refill bottoms only (not mineral top portion) in filter trap, set on lowest setting. Any suggestions or thoughts?