Can you spray Diatomaceous Earth to the filter membranes?

I would like to hear experts' experiences with how to best apply DE to your filter membranes.

1. I have a 2-speed pool pump, with full at 1.5 HP. After I clean my DE filter, I dump the DE through my skimmer. In order to achieve a good even coating on the membranes, is it better to do this while the pump is running on low speed or high speed?

2. Is there any technique whereby before you put on the filter tank cover (a.k.a. upper half part of the tank) you would spray diluted DE at your membrane, again, to achieve a good even coating? Does anybody do that or is that not recommended for whatever reasons?

Thank you for your help.

Either high or low should work, make the slurry and add it to the skimmer, adjusting for the flow so that it doesn't end up going in too quickly and ending up coming out the skimmer mouth and into the pool.

Never found a way to 'pre-spray' the filter:(

When I first started working on my pool, I didn't know any other way, so I dumped scoopfuls of DE into the skimmer. Later, a friend who sells DE for commercial applications told me to mix the appropriate amount of DE with water in an old, clean chlorine bucket. Put enough water to get the consistency of milk, whole or skim.;) Pour it into the skimmer slowly. I take a minute or two to pour in five or six gallons of slurry. I was told this method would help prevent blasting the grids with more DE than they could handle and would promote a more even application. Don't know if it works better, but that's how I do it now.

Just my opinion, but I would think your low speed would allow the DE to spread more evenly.

Hal

Thank you for the replies.

I have tried both dumping the powder as well as the diluted DE into the skimmer and very slowly. Sometimes I'd notice that there'd be some that go back out through the pool returns, i.e. back into the pool.

That's why I was wondering how people ensure the DE gets applied evenly to the membrane.

Is it normal for some DE to go back into the pool? Or does that mean there's something wrong with the filter or with how it's re-assembled?

I don't think there's anything wrong with your grids. I see evidence of a little blow by in my pool, too. When the grids are clean and suddenly this almost liquid material flows to the grids, I don't think we can expect it all to be stopped immediately. That's when the pores in the grid material are the largest, before any DE is coating them. I think you're doing it right.

Hal

Quote:

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Originally Posted by Sumo1

I don't think there's anything wrong with your grids. I see evidence of a little blow by in my pool, too. When the grids are clean and suddenly this almost liquid material flows to the grids, I don't think we can expect it all to be stopped immediately. That's when the pores in the grid material are the largest, before any DE is coating them. I think you're doing it right.

Hal

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Thank you for the reassurance, Hal.