labifleanswered grow question 6y ago Hey gardener! If you let it sit for 24 hours, you'll get rid of the chlorine, so that's already a start for filtering. Don't bother filtering if your water is soft; you should have some chlorine and a few things like calcium and magnesium, but in small amounts. At the same time, if you can filter, why not? Good luck to you, bella ciao!