Where and how do you apply the DE to the pool filter?

Start by cleaning the entire filter. Disassemble and hose off the grids. Without this process you are just guessing as to what is already in the filter. Reassemble. The formula is usually on all DE bags . . . you have to know the square footage of the filter. This is usually stated on the name plate of the filter. Such as 36 sq.ft; 48 sq.ft.; With Hayward it is usually 4800;3600 etc. An easy to remember formula would be take the sq. ft, divide by 5, this answer will tell you how many cans or scoops of DE are dumped into the skimmer. Example: 48 div. by 5 = 10 rounded off. Note: if your filter is more than 1 yr old ~ your filter will have a residual of old DE left in the tank after each Back Wash ~ it never totally removes all the old DE and dirt during a B/W ~ this accumulates so that is why you clean out the filter tank. This formula will give you an even and uniform coating on all grids ~ the DE is what is doing the filtering not the cloth grids.

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