Let's be more specific. Pool filter DE is manufactured in such a way that it contains up to 90% free silica, VERY hazardous to inhale. It is also virtually useless as a pest control agent, due to this manufacturing process. Those are two important reasons that it should never be used in any way but for filters.

Food grade DE contains a very low % of free silica....less than 5%. But its physical structure makes it lethal to many arthropods. It should not be used widely in the garden for that purpose. We should avoid inhaling food grade DE, as well.

I use food/horticultural grade DE in my garage, which can be a haven for black widows and brown recluse spiders. Inside, avoid using it on carpets (for fleas) which must be vacuumed....making it airborne. Inside cupboards, behind appliances, in the pantry are all useful locations as long as cleaning is done with a damp cloth or mop.

I never recommend it for garden use because of the 'collateral' damage to beneficials.

Thanks for the most excellent reminder, summer.....I'm just giving people the reasons WHY.

Diatomaceous Earth is a silica. Food grade DE must have very low levels of Arsenic and Lead.
http://www.absorbentproductsltd.com/food-grade-diatomaceous-earth-vs-pool-grade.html

Here is a link that might be useful: About Diatomaceous Earth

Hi Rhizo_1, you are one of the most resourceful members of our forum. I sincerely respect your contribution to the forum.

I have a question about DE. I have been using DE cat litter for my container plants. Most of the cat litter available here are DE cat litter with perfume or without. I think they are not harmful to the pets and people. Is it harmful to the pets and people? Here is a picture, the big one is also DE I think but I am not 100% sure :-) and the small one is DE cat litter I use. This cat litter is use by many bonsai growers too.

{{gwi:1187088}}

It is not very dusty, I never found any powder in the bottom of the bag. Perlite available here are very dusty.

Caelian

Hi Kimmsr, thank you for the link, I bookmarked it. We got a lot of resourceful members here, they are the lifeline of our forum.

Caelian

Cailian, there are many uses of DE, all of which are dependant upon how it has been manufactured. The large particles used for cat litter and soil conditioners are calcined (heat treated) and rinsed so that there is little dust. This is especially true for the cat litter product. Lots of people use this form of DE for their container growing and swear by it.

We aren't talking about clay cat litter, everybody.

The uses of DE should never be confused with each other. Pool filter DE, for example, consists of very small particles, heat treated, and is full of dust.

If you still have questions, just let me know. DE seems to cause confusion.

Hi Rhizo_1, I was eagerly waiting for this information. Everything is crystal clear now, thank you very much for your time and the information.

Caelian