I'll let someone else advise you about the equipment. My guess is that the first two might be ok but the third one is too big. If you do go with that one, you'll have to replace the sand. A sand filter gets very gunked up with Baquagoop as we call it.
A couple of things to have on hand are several gallons of plain, unscented bleach, some muriatic acid to lower the pH, some baking soda, approximately 5 lbs. of CYA (cyanuric acid -- sometimes labeled as conditioner or stabilizer. If the ingredient is cyanuric or isocyanuric acid, it is the right stuff.)
Bookmarks