New to DE filters...need some help

[Phillbo]

My DE filter runs around 12PSI when freshly back washed. I back wash when it gets to 20PSI and add 4 coffee cans of DE. Been using this system for years and pool is crystal clear. Don't get too hung up on the exact psi increase etc... I'm not sure of the difference between pool grade and food grade DE other than you can use food grade in your garden to control crawly thangs

Throw a couple cans in and forget about it until you see a pressure increase and then start from scratch .

[waste]

Welcome to the Forum!

I wrote the "use and care for DE filters' and it was based on the pools I saw as a service tech and was meant to tell folks how to avoid the problems I had to go fix.

You most certainly have to replace DE after you backwash the filter!!! (it's in the stickie)

As for frequency, I'll stick to what I said, "when the PSI rises 8, it's time to backwash and then add ~80% of DE that you would, when the filter is new or manually cleaned" - however, if you want to backwash more frequently, you'd need to increase the % (of a fully clean filter) up from 80%.

I'm sorry that I don't know anything about 'food grade' DE, perhaps someone else does and will chime in.

I hope this post helps you a little, if you need more info - I'm here on weekends and there are a number of other folks that will help you