Quote Originally Posted by cleancloths
PatL34 - while that method may work for you it uses a hell of a lot of water. I have a DE60 and find it much more cost effective to open it and hose it down rather than backwashing it.
I agree, it is better to disassemble, clean, then recharge with the full amount of DE.
When I first got my new pool running I did the backwashing method to clean the plaster dust and it would drop the pool water about 2 inches (in a 20,000 gallon pool). The pressure would return to normal but raise again realitively quickly (days). A few weeks later I disassembled the filter and discovered that a huge mass of DE and old plaster dust cacked at the bottom. Now I only disassemble to clean. It doesn't take that long and I know exactly how much DE to add afterwards.

P.S. I have the Pentair FNS Plus (60 sq-ft) and it takes 6 lbs DE when empty. If you have the 48 sq-ft model you shoul donly be adding 4.8lbs. If you have another brand, check your manual.
Good Luck