We have a bunch of DE that the old owners left. What is the equivalent for the BBB method? Just wanted to hopefully re-use some chemicals that the old pool owners left us..
DE
- Thread starter precator
- Start date
DE is for the filter, not the water. Assuming they didn't change to a cartridge or sand filter, at some point you'll need it. Save it.
The BBB equivalent for DE is DE. 
You can keep that and add it to your DE filter as you backwash and need to.
-- Pete
You can keep that and add it to your DE filter as you backwash and need to.-- Pete
loughps said:The BBB equivalent for DE is DE.
-- Pete
When do I know if I have to add the DE?
First we need to know if you have a DE filter like frustratedpoolmom asked. There are reasons to have it when you don't have a DE filter. But, on the assumption you do, when you backwash a DE filter, all the DE goes out the waste port with the water. When you switch it back to filter, you have to recharge it with more DE based on the model filter you have.
If you haven't started reading it yet, you'll find a lot of useful information in Pool School (big button at the top right of the page.) Feel free to continue to post your questions. For most people it takes a combination of reading pool school and asking questions to get the hang of it.
-- Pete
If you haven't started reading it yet, you'll find a lot of useful information in Pool School (big button at the top right of the page.) Feel free to continue to post your questions. For most people it takes a combination of reading pool school and asking questions to get the hang of it.
-- Pete
You only add DE after you backwash or teardown & clean your filter.precator said:loughps said:The BBB equivalent for DE is DE.
-- Pete
When do I know if I have to add the DE?
Diatomaceous earth particles are like microscopic sponges. It coats a fabric grid and the water goes through these tiny passages and all the pollen, dust, dead skin, algae carasses, etc get filtered out.
Typically, when the filter is freshly cleaned, you look at the pressure gauge. That is your baseline. When the gauge goes up 10 psi from that, it's time to backwash. If you notice the pool is looking cloudy and the water coming out the returns doesn't look as strong as it used it, that's another sign it's time to backwash.
I took my filter apart a few months ago just to have a look at the grids and physically clean them so I would know the baseline pressure for my filter. I had no idea how long it had been uncleaned, as I only moved in about a year and a half ago. Now I know, and there's a mark on the gauge.
The SM 20-2 is the multi-port valve. That particular multi-port valve works with several different filters, so we can't tell just from that how much DE you need to use.
You can find the owner's manual here. The amount of DE depends on which model you have and is found in Table 2 on page 5.
-- Pete
-- Pete
Much closer. The FNS Plus comes in several different sizes. The 24 takes 2.4 lbs of DE. The 36 takes 3.6 lbs of DE. The 48 takes 4.8 lbs of DE. And the 60 takes 6 lbs of DE. All of those numbers are for a full recharge after the unit has been throughly cleaned. After a backwash you should use about 80% of that quantity.
I just re-started the filter and PSI is not going up nor is there any water going out from my return jets. Did i do something wrong? I changed the setting from backwash to regular..
What position did you turn the multiport valve to, after backwashing? It should be on "filter" for normal operation.
Please read this
Please read this
