I recently purchased a new house that came with a 13,000 gallon IG, vinyl lined pool. I'm waiting on my test kit to arrive, but so far I've been adding bleach and just using the test strips to check chlorine level. After spending about a month scooping leaves out of the pool every evening, and then vacuuming almost constantly for a week, I finally have the pool free of debris and clear. At any rate, I was reading through the pool school articles and the article on filter types led to my question. I actually have both a Hayward sand filter with a multi-valve and a cartridge filter (in that order). Should I actually allow the water to be filtered through both, or would I be better off setting the multi-valve to recirculate and bypass the sand filter? Thanks in advance!