How to measure DE for filter

[Emarshbuck]

I'm not sure I'm using the correct measure of DE when I reload my filter after a backwash. I'm using the 1lb 13oz blue plastic Maxwell coffee containers. My filter is a Pentair FNS Plus 36. How many containers of DE should I use on startup (after I have cleaned the filters at the start of the season) and how many after I backwash during the season?

I am seeing very tiny pieces of debris on top of the pool, and am worried that the filter is not loaded properly. Of course, the pool sits under a live oak, and there is constant material falling in especially during a rain storm or even mild winds.

thank you,

ed

 

[JamesW]

Each pound is about 48 fluid ounces (volume). Your filter needs about 4 lbs on a fresh start and about 3.5 lbs after a good backwash.

 

[OldPoolMan]

Also, 1lb of DE is equal to 2 1lb coffee cans. DE is 1/2 as heavy as coffee.

 

[Emarshbuck]

Also, 1lb of DE is equal to 2 1lb coffee cans. DE is 1/2 as heavy as coffee.

This is good info. So I can calculate that a 1lb 13oz container is actually about 15 oz of DE, so if I need 3.5 lbs to recharge after a good backwash, I'll need roughly 4 containers of the containers.

Is there a danger if I over charge the DE?


thx

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that is, "4 containers of the DE"

 

[JamesW]

The amount of de isn't critical, but you should try to get close to the recommended amount.

 

[chiefwej]

I weigh it on a postage scale. That way I know I have the right amount.