What is DE?

Well - I've read about people adding DE to the skimmer, in order to help their sand filters do a better filtering job. I'm pretty sure that DE doesn't stand for Dangling Eurethra :eek: ...but what is it and what does DE stand for?

Thanks,
C

It's easier to show you this link than it is to explain it :)

http://en.wikipedia.org/wiki/Diatomaceous_earth

It's diatomaceous earth. Essentially it's skeletons of microscopic creatures that appears as a white powder. It's the critical element that allows DE filters to function. DE filters are the finest filters sold for pools, filtering down to something like 2-5 microns. Cartridge filters filter to 20 microns, and sand filters to about 50-60 microns. Some of the most expensive robotic cleaners (Aquabot, Blue Diamond, Dolphin Dynamic) can match the DE filter at the 2-5 micron range, but they aren't daily filters.

But we also can add a little DE to sand filters to get the water a little clearer. I was one of the first to experiment with this--Poconos led the way. It's very inexpensive to do: I've been using one 10 # box for 2 seasons, and am about to open the 2nd 5# bag in the box--and the 10# cost me $8. The results, combined with a few other strategies, have gotten my water from very clear to crystal, crystal clear.

DE also is excellent for ant control. Apparently, it's quite deadly to them--something about the sharp edges on the powder grains I think.

Here's some relative particle sizes.
Al

Attachment 663

Attachment 664

As you can see, Al has WAAAAAY too much time on his hands!

Thanks for the clarifications - I really appreciate it.

Where do I buy this? And are there different "types" or just DE...period?

Thanks,
C

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Originally Posted by CarlD

DE also is excellent for ant control. Apparently, it's quite deadly to them--something about the sharp edges on the powder grains I think.

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DE is a desiccant. After the sharp edges cut through their "skins", the DE literally sucks the water out of the ants' bodies. Using it makes me feel like I'm engaging in chemical warfare.

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Originally Posted by Candyass

Thanks for the clarifications - I really appreciate it.

Where do I buy this? And are there different "types" or just DE...period?

Thanks,
C

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Any pool store. There's DE and a new, expensive fibrous alternative to it which is NOT DE.

Quote:

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Originally Posted by Candyass

Thanks for the clarifications - I really appreciate it.

Where do I buy this? And are there different "types" or just DE...period?

Thanks,
C

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There are several grades of DE: Pool, Horticultural, Food, etc. I'd use only pool grade in your pool filter to be safe (though I have no idea what would happen if you used another grade).

As Carl said, pool stores will have the right stuff. So will Wal-Mart, Home Depot, Lowes, etc. (in the pool season).

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Originally Posted by KurtV

There are several grades of DE: Pool, Horticultural, Food, etc. I'd use only pool grade in your pool filter to be safe (though I have no idea what would happen if you used another grade).

As Carl said, pool stores will have the right stuff. So will Wal-Mart, Home Depot, Lowes, etc. (in the pool season).

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Thanks. I only know about pool DE. Even at expensive stores it's fairly cheap, especially if you plan on using it to augment your sand filter. As I said, one 10# box was $8 and I've barely used half in 2 seasons.

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Originally Posted by CarlD

Thanks. I only know about pool DE. Even at expensive stores it's fairly cheap, especially if you plan on using it to augment your sand filter. As I said, one 10# box was $8 and I've barely used half in 2 seasons.

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Does anyone use or have any thoughts on using DE to augment cartridge filters? I have a Jandy 580 Cartridge and would love crystal crystal clear water! :)

Thanks.
CARLO.

Yeah, we've had some discussion on it and it's a really, really BAD idea. Apparently the DE clogs the filter permanently....

But I also gather that the fibrous alternative to DE works very nicely in cartridge filters. Maybe something about the fibrous stuff being similar to fibrous paper in the cart?

Pentair recommends adding DE ONCE to a new cartridge to increase filtering ablilty. I haven't done it but I mght consider it next time I buy a new cart to see if it has any impact on filtering ability or cartridge life.

Interesting
Can you tell me how to add this. I went from a DE filter to a Sand Filter. How much DE to add? I assume thru the skimmer and how much PSI bump? Mine stays on 11 after backwashing. And do i need to add more after backwashing and does it ruin your sand prematurely?

Thanks
Mike

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Originally Posted by mikemedic

Interesting
Can you tell me how to add this. I went from a DE filter to a Sand Filter. How much DE to add? I assume thru the skimmer and how much PSI bump? Mine stays on 11 after backwashing. And do i need to add more after backwashing and does it ruin your sand prematurely?

Thanks
Mike

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Mike,
Usually people start with about 1/4 or 1/3 cup. You can make a slurry by mixing it with water in a bucket and adding it to the skimmer, or be lazy like me and just add it slowly to the skimmer.

After 20 minutes to 1/2 hour, you should see the PSI rise. The object is to get it to rise 1 PSI only. So you start with a small amount and take your time increasing it until you hit your target. That's the amount to use from then on after you backwash.

I've never heard of too much DE ruining the sand. If you add too much you just backwash it out and start again.