Pool problems on startup

[stma]

Just thinking out loud here, I would need to "coat" after every back wash ??

[stma]

@Ben, VERY much appreciate you sticking in here with me on this !! Quick question :: After 20 minutes of adding the DE, my pressure went up 2 pounds..... 40 minutes later (an hour after application) the PSI jumped 3 more pounds... Is more pounds a good thing and let it ride, or do I need to backwash and start again adding less DE ??

[PoolDoc]

I'd backwash at a 7 - 10 psi increase.

You need to coat after every backwash, because the DE is flushed OUT of the filter during backwash.

[michael3]

Hows your progress going stma? seems like it takes about 2/3 of a cup of DE to get 1-2 psi rise on my system. let it run all night and it has only risen about 5 psi. not sure if thats a good rise or if it should have climbed quicker lol, anyways I`m going to do like Ben suggested and wait till I get 7-10 increase then backwash and add more

[stma]

Ben had posted above about coating the filter::: Using 3oz per sq ft of sand surface... with my small 166 filter, Im putting in 4.5 ounces..WAY MORE than the 1/2 cup from the DE "thread." I backwash once the return loses most or all of its pressure... for me, that is a 6 pound rise... Just checked this morning, and this method is definitely working.... May be a slower than normal process, but like yourself, I am optimistic about this !!
I'll spend the day today hanging at the pool, and doing the backwash-- dosing "thing"... Hopefully tomorrow I'll see a little more than just my reflection when looking into the water !! : > LOL

[michael3]

If I want 3 oz of weighted DE and I have 3 sf or 24" filter that = 9 weighted oz of DE to coat? I don't have a scale lol any idea how 9 oz dry measures out in a regular liquid measuring cup

[stma]

OK... 1 LEVELED Cup is 2 1/4 ounces..... so 4 Cups would be 9 oz.... I used half that amount for my smaller filter...I slurried with approx 1 gallon of water and slowly poured in..... Again, i based my decision to backwash, by the outflow at the return..... i am backwashing every few hours...probably dont need to do it that often, but I do like the results im getting....

[michael3]

Wow, I've been putting 2/3- to 1 cup, no wonder it takes 6-8 hrs to get the 8-10psi rise. I wonder if that little is still filtering but just slower? Does more filter faster or just raise psi quicker