Diatomaceous Earth, To Eat or Not To Eat, That Should Be Stated!

[Concorde]

I just cleaned up a dirty pool and there is a bunch of dead algae that needs to be filtered out. I know from past experience that it takes quite a while and/or some more big chlorine adds to filter or burn it up. After reading a little about DE in the forums, and then the Pool School's article on DE, I went out and bought a 25lb bag at Tractor Supply. I bought a food grade quality bag.

I went back to the forum to see if I could find some better details about how much to expect to need in a sand filter. And I found that some say you're not supposed to use food quality DE in a pool.

This Is Not Stated In The Pool School Article. Add DE to a Sand Filter - Trouble Free Pool

So I'm a little frustrated. I've used a cup and a half. Maybe I can use it in the garden, but I already have another powered non-toxic bug killer, Cimexa, for that.

Since there are so many forum posts that do not mention food quality vs pool DE, is it honestly really going to matter? Or is it just a matter of just a better idea to use the rough pool grade kind? I need honest answers here. If so, why isn't it mentioned much in the forums? It's a pain to return and find another.

 

[mknauss]

"Gardening DE, while safer to handle, has not been heat treated and therefore is not suitable for use in pool filters."

Directly from the DE article in Pool School.

I am not sure why that is -- we need another member with knowledge on that to chime in.

 

[Oly]

From...... What’s the difference between Food Grade Diatomaceous Earth and Pool Grade Diatomaceous Earth?


How diatomaceous earth is treated determines whether it’s Food Chemical Codex Grade or Pool Grade (also known as filter grade).

Pool Grade diatomaceous earth is calcined, meaning it has been heat-treated and activated for use in filters. The high temperatures further harden the diatom exoskeletons, creating a better filtering agent. This process also turns the silicon dioxide within the DE into crystalline silica. Some calcined DE products, including pool grade diatomaceous earth, can contain high concentrations. Because crystalline silica is dangerous and can be harmful to both human and animal health, Pool/Filter Grade diatomaceous earth should only ever be used for filtration.

A majority of Food Chemical Codex Grade (Food Grade) DE products, on the other hand, are uncalcined and are largely composed of amorphous silica. Food grade diatomaceous earth products contain less than 1% crystalline silica. This can be used in animal feed and for insect control. Food grade DE must also meet heavy metal content specifications: it must not contain more than 10mg/kg of arsenic and 10mg/kg of lead, otherwise it might be classified as “feed grade.”

 

[Concorde]

I love this site, but Somebody really needs to put this information in with the How To page about adding DE.

 

[mknauss]

Noted -- we can expand the warning in the DE article.

@Leebo

 

[Concorde]

Thank You.

I don't have any problems keeping the DE I bought, as I could use it somewhere sometime I'm sure.

Thanks to this site, I'm really only aware of Leslies pool supply in this area (Katy, TX). I guess I'll just go there and pick some up. Unless there is another recommendation. I can get impatient though.

I bought solar salt pellets at Tractor Supply, $5.98 per 40lbs. Was very surprised at how much salt went up in the past year.

 

[mknauss]

DE is normally available at Home Depot, Walmart, etc for pools.

 

[Richard320]

Thank You.

I don't have any problems keeping the DE I bought, as I could use it somewhere sometime I'm sure.

I put gardening DE into mustard and ketchup bottles from the 99¢ store. Makes it really easy to draw rings around plants in my vegetable garden. It kills snails and slugs and insects that cross it. I've also been known to give things a good dusting with it. It seemed to get rid of whatever was chewing holes in my squash leaves. It just rinses off when the vegetables are ripe.

 

[Concorde]

Thanks. Just what I thought I might use it for. Got late to doing things in the yard this year, including the pool. But looking forward to a garden this fall.

Hopefully a 1 1/2 cups isn't going to do much denigration to the pool. Off to HD I go!

 

[Concorde]

I also have a friend that has a humming garden right now. Wonder if she needs it.