DE in the pool--very cloudy

Shelley N

Well-known member
May 1, 2007
199
Denver, Colorado
#1
I decided to backwash the filter. Even though the psi was only up 2, I hadn't backwashed all summer and I thought it was time. After the backwash and rinse, I added between 1/2 and 1 cup of DE. I watched it come billowing out the return :(. So now the pool is cloudy. Overnight most of it settled on the bottom, so I got in there today and vacuumed. That was a bugger to do too as it didn't want to leave the bottom of the pool with just the mere sweep of the vacuum as we have a sort of dimpled vinyl bottom so I had to do a sort of "push broom" sweep back and forth to get it up. All that seemed to do was stir it up, as it is cloudy again and doesn't appear to be getting stuck in the filter as planned. It is a 21" sand filter with a 1.5 hp pump. This is just our 2nd season with it. When I hooked everything up in the spring, the sand in the filter looked beautiful, clean and without any veining or crust. We don't get a lot of junk in the pool, just the occasional bug.

Since it's not clearing, I'm not sure how to clear up the water. It settles over night, I vacuum it into a cloud and we repeat this process daily. Is there a filter pack or something I can put somewhere to catch it? Do I need to stop everything and look into the filter? Ugg.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,461
SW Indiana
#2
You've got a filter problem. Maybe the multiport gasket is bad and not routing all of the incoming water through the sand.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,461
SW Indiana
#4
Shelley N said:
Can you tell by looking, or only by the symptom?
You have to disassemble the valve, which isn't big deal. You might just try backwashing again in case something got stuck in the gasket.
 

Shelley N

Well-known member
May 1, 2007
199
Denver, Colorado
#5
Well, today makes a week since the DE addition and I've still got the cloud. Every morning there are traces of it on the bottom that the ladybug gobbles up pretty good, but there is still the haze. Is this when you are supposed to use floc? What are the pros/cons to that stuff?

Thanks all.
 

waste

TFP Expert
LifeTime Supporter
Mar 29, 2007
4,160
Coastalish 'down easter'
#6
Shelly, there are times to use a floc and times to wait before doing so. In your present case, I'd hold off on the floc until you open the multiport and make sure that the 'spider gasket' (a/k/a wagon wheel) is in good shape - as per John's suggestion. Ordinarily I'd suspect the filter but you say that you checked the sand recently and it was good, therefore I think John hit the nail on the head and that the multiport is 'bypassing' for some reason. Please make sure that the multiport is functioning correctly before adding a chem which may cause other problems, floc is a last resort. :)
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,461
SW Indiana
#9
robrinker said:
I'm still new to the pool thing, but I thought that sand filters used sand and NOT DE. Are there filters that you put both in?
Some people add a small amount of DE to their sand filters. It appears to make them filter smaller particles, much like a dirty sand filter does. It goes away when you backwash.
 

Shelley N

Well-known member
May 1, 2007
199
Denver, Colorado
#11
Okay, got my DH to help me remove the top of the filter. Looked like the sand we put in, but when you touched it, it reminded me of a layer of lint. Also the sand was 10-12 inches below the top of the filter. I did install the correct sand and the correct amount (200#) last year, but I wasn't around when it was installed, so I'm not sure this is normal depth or not. I did not feel any crust, nor were their any visible holes in the surface indicating a vein, however around the very edge of the sand there seemed to be a different pattern, I'm guessing above where the laterals end. Almost as if it got more flow there and turned the top over so it didn't collect the "lint". We took pictures, but of course the hubby has them in his camera at work. The water on top of the sand was crystal clear, but when we took the drain off at the bottom it was cloudy like that's where the DE was. We put the top back on, backwashed, rinsed and started her up. The gasket spins easily, there wasn't anything stuck anywhere and unless I take it apart, I can't tell if it's doing the cycle it says it's doing. I'm amazed that the manual does not say what each position is as the sticker is suffering in the weather and won't be with us much longer.

How far from the top of the filter should the sand be? Can this be my problem?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#12
It is normal to have some headroom at the top of a sand filter. There needs to be enough space so that the water flow during backwashing is not enough to wash the sand out the top. The exact height varies from model to model, anything from 6" to 14".
 

Poseidon

Well-known member
May 24, 2007
148
Houston, Texas, USA
#13
Shelley N said:
Okay, got my DH to help me remove the top of the filter. Looked like the sand we put in, but when you touched it, it reminded me of a layer of lint. Also the sand was 10-12 inches below the top of the filter. I did install the correct sand and the correct amount (200#) last year, but I wasn't around when it was installed, so I'm not sure this is normal depth or not. I did not feel any crust, nor were their any visible holes in the surface indicating a vein, however around the very edge of the sand there seemed to be a different pattern, I'm guessing above where the laterals end. Almost as if it got more flow there and turned the top over so it didn't collect the "lint". We took pictures, but of course the hubby has them in his camera at work. The water on top of the sand was crystal clear, but when we took the drain off at the bottom it was cloudy like that's where the DE was. We put the top back on, backwashed, rinsed and started her up. The gasket spins easily, there wasn't anything stuck anywhere and unless I take it apart, I can't tell if it's doing the cycle it says it's doing. I'm amazed that the manual does not say what each position is as the sticker is suffering in the weather and won't be with us much longer.

How far from the top of the filter should the sand be? Can this be my problem?
If the correct amount of sand was put in last year, the "freeboard" (space between top of sand and top of filter) should be ok. The lint you spoke of is normal, and backwashing should remove most of it. The DE "should" get trapped in the filter .... unless you are running the filter in "recycle/recirculate" mode, in which case the water (and the DE) would bypass the sand bed and get blown into the pool. To remove the DE from the filter, backwash then rinse. To get the DE out of the pool, you can do one of two things 1) vacuum while running in "filter" mode to transfer the DE into the filter 2) vacuum to waste.