Hi TFP! I'm a new user - first post here We bought our house last year - has a 20K gallon pool, plaster. Pentair DE filter. Other than issues with our Polaris 280 last year, super easy to maintain, had a blast!
This year, I'm a bit stumped. Our pool has been dirtier than usual. We've done a bit of backyard reno, so I initially chalked it up to that, but now I really don't know and would like the advice of the fine folks here at TFP!
So we ripped out some bushes In May and leveled a bunch of dirt. We laid down around 100 sq ft of Oklahoma flagstone, and used normal Quikrete mortar to fill in the gaps. Also had a pergola/arbor installed. Pic: https://www.facebook.com/photo.php?f...5&l=271c388c39 - pool is to the bottom right of the picture, you can see the skimmer basket cover
We had been seeing more debris on the bottom than usual. Looked like a sand color, also around the same consistency. Most of it accumulates around the return jets, so I'm assuming it's coming back from the return jets. I initially thought it was dirt from leveling the ground to lay the rock. Then thought it could have been from the flagstone or the mortar or the pergola. We've had about 10 good rains since then, and it's been about 4 weeks since we've completely finished all work with the rock/mortar. I'd have figured any residual dust would have washed out by now? All edges slope away from the pool, so I have a hard time believing even if it was that debris, it was washing into the pool. I clean out the pool pump filter weekly, and drain the skimmer baskets at least 2-3x weekly.
I've backwashed the Pentair twice since then. The second backwashing was last Saturday. Each time I backwashed I left the pool pump running about a minute and a half with the BW valve open. Our pool guy told us initially 20-30 seconds, but a few YouTube videos recommended a minute.
I looked up a few YT videos and completely disassembled the Pentair, including removing the drain plug and taking out each grids/thoroughly washing out the container. There seemed to be more "gunk" on the bottom - maybe DE, maybe what appeared to be the sand junk kind of clogged up at the bottom. I had to remove the drain plug, poke the hole and spray it with water just to get it all out of there. (I had previously disassembled the Pentair back in late April and given it a good thorough cleaning - I don't recall that much DE/sand stuff at the bottom) My initial thought before opening was that the grids probably had a hole in it, but I inspected each one and they still looked pretty new. I did see some debris on the inside of the grid though...tried to wash it out as best as I could.
Reassembled it last Sat. Pool does look cleaner, but we're still seeing some brown light sand debris near the return jets. Less than it was, but still there. Any advice for a newbie? I'm just completely stumped...I've looked over YT and these forums and haven't had a lot of luck piecing it together, other than cleaning out the DE filter. Am I missing something obvious? And should the de/sand stuff collect at the bottom of the filter even after backwashing it out, or should that all have been swept out? (IE, maybe the backwash pipe is clogged, or I need to backwash it longer?)
Any suggestions the pros here have I would love to hear. Thank you for the help.
-Frustrated Guy with a 6 month Pregnant Wife That Wants Him to Fix Our Pool, aka Melvin