well 1st how big is the filter?...if it's a hayward around 200 lbs...jacuzzi...250lbs...for the norm. inground pool witha one horse pump...no more the 250lbs...good luck
answer.
Check the label on...
None,,type s mortar already has sand.Type S is sometimes specified for masonry at or below grade, but offers another quality. S has high compressive strength (1800 psi) but adds high tensile bond...