How much DE to add?

A very basic question....I was wondering what the formula is for adding DE to the filter. A lot of people talk about using a 1 pound coffee can. How many 1 lb cans equal 1 pound of DE? How do you know how much DE to put in after backwash?

Thanks for the help! This forum is the greatest. I have learned so much!

Mary

Mary, it's my understanding that a 1 lb coffee can holds 1/2 lb of DE. On the back of a bag of DE at an owners' house last week I believe it said that 4 cups = 1/2 lb (a little work with my calculator informs me that 8 cups would equal a lb:D ) Some stores sell DE scoops that when full hold either 1 lb or 3/4 lb of DE for quick measuring.

After a complete backwashing, you should add ~ 80% of the startup amount, ie - if the filter takes 6 lbs when new, add 5 lbs after backwashing. I've got a couple of threads I usually link to for this question - I haven't had to do it in a while so don't have them right in front of me, but if tomorrow is the rain day I expect, I'll take the time to look them up and get you the 'cross links'

There are also cheap, plastic DE measuring buckets at most poolstores. These normally measure 1lb of DE. Both Leslie's and NAMCO have them in my area, plus all of the LPS as well.

Thank you for all of the info! I will check out Leslies to pick up a new scoop to take the hassle out of measuring.

Mary