DE to sand filter?

[Digger]

I am getting ready to change the sand in my tank. Do I put any DE in with the sand as we are doing this, or is this for later on when older sand is not doing its job as well? I know I am being a pain, but I want to do things right from the start after 14 plus years of Baq problems I want things PERFECT! LOL I know that is not reality, I am kidding, but I want to do the best I can to ensure we have a clean, sanitary, cheaper running pool. We have sunk TOO MUCH money into this beautiful, refreshing hole in the ground, smile!

[AnnaK]

From my understanding of reading the posts of those people who've added DE to their sand filter, they add a very small amount through the skimmer on top of the sand. IOW, the sand is in, then they add the DE. The amount would depend on the size of filter, I imagine. You're looking for a pressure change of just 1 psi, so go slow. I seem to remember 1/4 cup of DE to start with and keep an eye on the pressure gauge. How long this takes I don't know, I've never done it.

If the pressure goes up more than 1 psi, backwash and rinse. That'll flush the DE out so you can start again with a lesser amount.

As to your other post about pea gravel, have you tried a search on "pea gravel" and "laterals"?

[Digger]

Thanks Anna for your response and help. I was doing searches for sand changes, sand, etc. I will try that also. I SO appreciate your help and response. I try not to be an impatient person, but I don't very often have the help to do a major task, smile! I want to be able to take advantage of that, and the day is getting away from us. THanks again!!

[AnnaK]

Janet gave you some excellent advice about the process. I would like to stress something she said because so many people seem to forget to do that, or not know:

RINSE after backwashing.

The rinse cycle should be about 30 seconds. It reverses the water flow inside the filter and packs the sand back down. If you don't do this you WILL get sand in your pool through the returns.

Be sure you have plenty of water in the pool before you begin a backwash/rinse cycle. It tends to take a considerable amount of water, depending on how dirty the filter is. I usually do it either right after a good rain when the pool is over-full anyway, or I run the hose while I'm cleaning the filter.

Don't skimp on the rinse cycle or you'll be sorry You can tell when it's done packing down the sand by how much/how little sand remains in the sight glass. A few grains means you're done. Too many to count? Keep rinsing.

[aylad]

Be sure you have plenty of water in the pool before you begin a backwash/rinse cycle. It tends to take a considerable amount of water, depending on how dirty the filter is. I usually do it either right after a good rain when the pool is over-full anyway, or I run the hose while I'm cleaning the filter.

Good point, and something I usually forget to check until I'm in the middle of it all and hear the skimmer sucking air!

Janet

[AnnaK]

Heh! Don't I know it!

Earlier this year I posted here about air in my pump pot. Al helped me look for leaks in the plumbing. My husband, bless him, took all the plumbing apart, wrapped it with Teflon tape, lubed O-rings, worked his fingers to the bone. He's a sweetie!

Then I got the bright idea to add some $#@! water to the pool. Oh yea! No more vortex in the skimmer, no more sucking air.

Sometimes, it's just too easy.

[aylad]

Do not put DE into the sand filter as it is filling with sand. Only use pool filter grade sand. You need to partially fill the filter with water before you add the sand, then when you add the sand be careful not to break or crack any of the laterals--those little "fingers" that stick out from the center. When you get ready to start up the pump after the filter is filled with sand, MAKE SURE YOU START IT UP IN BACKWASH MODE. I learned this the hard way, and it took weeks to get my pool cleared up again!!! Let it backwash all the little fine dust out before you switch it to rinse and then to filter. Remember not to switch positions on the filter with the pump running--you must turn it off before changing positions.

Later on, if you find that you're having filtration issues, then you can add a little bit of DE to the filter to help catch the smaller stuff--but it washes out when you backwash, so it's a repetitive thing.

Janet