Few things are more frustrating than to see the very stuff that is supposed to be filtering your pool water leaking into the pool. The common culprit involved in DE powder going back into your pool is torn grids but there are a number of other causes as well. Here are a few things to check to help you troubleshoot this annoying problem.
Torn Grids
As mentioned above, this is probably the most common issue. Over time, small tears can develop in the grid fabric and provide
a gateway for DE to sneak into your pool. Carefully inspect all grids ; the good news is you can replace individual grids so if you find only one or two with tears, you do not need to replace the entire assembly.
When you check the grids, also take a glance at the plastic collars where they attach to the manifold. Even though the grid fabric might be intact, a crack in this small part would mean the entire grid needs to be replaced – sorry!
Some DE filters, like the Hayward Perflex, have “fingers” instead of grids. These tube-like tentacles can also crack and require replacement. Other parts to look at while you check the tubes are the bump shaft o-rings, diaphragm gasket, the top and bottom tube sheets, or possibly loose tube sheet bolts.
Cracked Standpipe
Over time, the pipe assembly inside the filter tank can crack and leak DE. Assess this part for any damage and while you’re there, check the associated o-ring. If the o-ring shows signs of wear, it might not be sealing properly and should be replaced.
Worn Manifold
The manifold is the cross-shaped top piece that holds the grid assembly together. There could be two issues here, either cracks in the manifold itself or a worn manifold o-ring. Try your luck to see if you can get away with replacing just a small o-ring or have to spend a bit more to buy a new manifold.
Valve Damage
If all of the filter tank internals are in tiptop shape, the valve on the top or side of the tank could be your DE-leaking villain. More specifically, the gasket inside the valve which can be cracked or worn through. A common cause of damage to this part is the pool owner changing the valve handle position while the pump is running (you know who you are).
Pump Suction Leak
Surprise! Your DE filter could be entirely blameless while its sidekick, the pool pump, causes all the trouble. A suction leak in the pump can push some DE into the pool via the skimmer or main drain when the pump is turned off. If you’ve already exonerated your filter and valve from any blame, inspect the pump for a suction leak. Some common parts to check are the lid o-ring, drain plug o-ring, and pump union o-rings.
If you still have an issue with DE in your pool after checking all of the above, you might need to have a pool professional come take a look. For those fortunate enough to have found just a torn grid or two, please be sure to check out our guide How to Replace DE Filter Grids.
Just replaced motor with a two speed motor. Works fine, but the first time i went to discharge some excess water by moving the valve to waste water, there was still some water coming out of the jets…and they all had de coming out too. Confused. Any recommendations?
Thanks
We have a brand new unground pool DE was leaking into the pool. the serviceman came, hosed out the grids( to check for tears) checked the o rings and found nothing. next filtering there was even more DE. Im so freaked out. There is an air bubble in the pump that he said was probably not a big deal bc it was brand new. If I pay for new grids ($450) and the problem persists what am I to do? I really can’t afford to replace every component of a BRAND new pump. The company that put the pool in is really not wanting to help us. Any ideas?
Where is the DE coming from? Can you see DE powder coming out of the returns or do you just see it at the bottom of the pool? When your pump turns off, does it lose prime?
If the powder is at the bottom of the pool or surrounding the main drain, your pump may be losing prime and backflushing all the DE into the basin. A pump losing prime could be the result of a tiny pinhole air leak on the suction side of your system. That air bubble in the pump strainer could be a sign of that. How to Identify and Correct Air Leaks
There shouldn’t be a visible air bubble in your pump basket. If there is it probably sucking air there. Male sure the gasket and area it sits on is clean and that you don’t cross thread the cap when you put it back on.
That’s not strictly true. Even healthy systems may have a couple of small air bubbles in the strainer lid. Dual speed pumps of variable speed models set to the low-end of RPMs may not fill the strainer put completely.
Hi Matthew,
Our gym recently opened the pool after draining and renovating it. A girl swam in it and noticed white powdery water. She said her lungs were burning and her eyes and told manager. He seemed unresponsive. She called health department and they closed pool down 2 days later while I was swimming in it for about ten minutes. They closed it down for new uninspected material and cloudy water.
They said prolly DE leaked in pool.
I’m wondering if swimming in a pool for the fifteen minutes I did is dangerous to my health.
The inspector checked chlorine and ph level the day they closed it down and they said those levels were okay.
DE powder is usually only harmful if breathed in. A breathing mask should be worn when adding the new dry powder to the skimmer, or handling it. If the DE powder was in the water, you wouldn’t have a danger of breathing it in unless you inhaled a bunch of water. I’m not even sure if that would have that much of an effect. DE powder is edible and is even sold in health food and vitamin isles.
DE is unlikely to cause the irritation described.
Thank you so much for your reply. I read DE has other uses but the type that is edible is different than the grade of DE used in pools.
So it seems the caution is when handling it in powder form. However I was swimming in it when the water was white and powdery looking due to the DE leak ( obviously problemsxwith the filter) I was most concerned with the DE leaky water getting in my eyes and whether the powdery water can cause any long term health hazards due to leaking in a pool. You seem to have a lot of knowledge with these DE leaks.
It can irritate the eyes, but I don’t think it would cause lifelong damage. If it was causing that much damage, you would likely be at a doctor’s office right now, instead of debating the possibilities.
You should be fine.
Hi Suzanne. unfortunately I have the same situation. what did health department say after the investigation? how do you or the girl feel now?
Please I need help!…I was emptying my pool (waste) for excess of water when I realized DE (???) coming out of the jets (a lot)…:( what can be the problem? never had this problem before.Thanks.
There are plenty of things to check, and they are all listed in the article.
Thanks and I’ll review the articles…:)
Hello Matthew, you seem like a knowledgeable guy! I backwashed my Hayward DE4820 this past Friday, added in my DE and went about my day. I went up to the Pool on Saturday and the Water was quite cloudy. I didn’t even think to check my filters. I added some shock because we had quite a bit of rain, thought maybe it was that. I went about my day… Saturday evening the pool looked like Skim Milk only a bit cloudier UGH!! I stopped my filter immediately and took the cartridges out to inspect. Sure enough.. Quite a few holes and rips! Not good.
I have no cartridges on order. Filter is off for the mean time. Hoping some it it settles to the bottom while I wait for delivery. On to the question…
Once new filters are installed. I will put in say 3 scoops? ( asks for 6 for initial) but if it will be filtering the DE from the existing water as well I don’t want to over load the pressure. I am assuming there are at least 4-6 scoops worth in the pool 🙁
WILL the new cartridges trap the particles or will I need to FLOCC on re circulation to help drop the DE particles, wait a 24-48 hours and vacuum to waste before I install the new filter grids? What would you recommend. All other parts are in good working order.
I’m sorry, typo. I have NEW filter grid set on Order, no “no cartridges on order” lol.
Name is Dan by the way, sorry forgot to put my name.
Matthew, I have a large DE filter probably a Hayward (at least 25 years old). January I replaced all the filters, the manifold and basically all the parts on the inside. I have taken it apart, cleaned it and put it back carefully and tight (3 times) … BUT I am still getting DE back in the pool, in fact nearly all of it. What else should I look at? It’s a fairly new variable speed Pentair pump too. So frustrating. But I didn’t look at the pipe that I hammer the manifold down to. Thanks.
When your pump turns off does it lose prime? By that I mean, does the water in the pump and filter backwash into the pool? if it does, then that could be the source of your DE leak. When your water backflushes there is nothing to stop DE from entering your pool. If the powder is localized around the main drain then that is the issue. I suggest checking your pool plumbing for air leaks.
I just bought EC 90 d.e. cartridge filter. When the filter cuts off , the earth comes back out of the skimmer .
Because that is a DE filter that does not use a multiport valve, you may want to install a check valve either between the pump and the filter or before the pump to prevent the backflush of DE powder.
Is this pump and filter system installed above the waterline of the pool? I’m pretty sure this is a filter meant for above ground pools, meaning there should not be backflush from the filter into the pool as it is usually installed below the waterline of the pool. Because the filter has no valve or built-in backwash valve, if the filter is above the waterline, the DE is able to drain backwards from the filter through your skimmer.
HI, I have a Starbright DE35 that is shooting DE into the pool. I’ve replaced all the grids inside, vacuumed it 4 times over the course of a week and I still have DE leaking int o the pool. Any thoughts on what the cause could be?
Have you checked the valve or the manifold for any defects?
Yes manifold and valves were all checked, would the little metal air relief cause this? I’ve had it replaced once before and it was fix in place as in didn’t move at all, now I can easily pull it off and on. I only ask because the last time DE was getting into the pool that peice had broken off
If it was a cause once, then it would be a cause again. If the air relief is loose, that means there is a gap somewhere the DE can find its way through
I have DE coming in to the pool, but it only seems to be doing it when I turn on my super pump for my Polaris. When I do this a large cloud seems to shoot out the line for the Polaris and a little bit seems to shoot out two of my other three return jets.
My grids were replaced last year, Had a new Multi-port valve the year before.
Thanks
Are you sure it is DE coming from the jets and not bubbles from pump clearing the polaris’ hose of air? This might sound crazy, but I have had someone do this before.
Experiencing same problems as above with DE going back into pool. Inspected grids for tears, standpipe for cracks and re-lubed the o-ring, and manifold looks good also. After a while we saw the pool full of DE powder and I pulled my hayward muti-port valve apart and saw the entire valve caked with DE. Spyder gasket looked good also. Any other things I could be over-looking? Thanks
You may be putting too much DE in. That would be my last guess.
Just installed a new Pentair FNS 60. After adding the DE, the pool is now very cloudy. Is this normal with a brand new filter or might there be a bad part/issue with this new filter?
DE powder should not be entering your pool, especially when there is a new filter. Before installing the filter did you remove the grids or manifold? Or do you remember any point during the unboxing and installation where a rip could have occurred?
Make sure you have the filter’s multiport valve set on FILTER and not RECIRCULATE. The recirculate setting bypassed the filter when would send all the DE directly back to your pool.
Hello,
I found a hex head screw underneath the pool pump debris basket,maybe from the impeller or diffuser,not really sure.What effect would this have on how it filters the pool?
If the screw was sitting outside the pump, underneath it, it likely is not from the impeller or diffuser. if the screw is sitting underneath the actual strainer basket it could be an impeller and diffuser.
Honestly, I don’t know what could happen to your pool because like you I do not know why it is from. If you want to find out, open the pump and look for and missing screws. It could be just a loose screw from a skimmer faceplate or from who knows where.
I guess I’ll have to open it up…thanks Matthew.
Hi there. I have a Hayward pump system with the fingers and this is the third year with this unit. This year the pump has done a nice job on pumping but the filter aid comes back into the pool as soon as I put the aid back in. I have had a Pool for twenty five years and this year is the first time I had to deal with this. I have to valumn all the time. I have taken the pump top off and take a hose and wash off the fingers and it does okay for a few days. Then it starts all over again. I have to pump the pool every day too. A bit frustrating at this time. I can look for tears in the fingers more closely but as of now it looks ok. Any thoughts
Thank you
Gene
I don’t think you mentioned algae in your previous message. But the haziness you are seeing in your pool may be dead algae and not DE. If there is algae in your filter, then you do not have enough chlorine in the pool to keep it away.
It sounds like you need to do a shock and algaecide treatment in combination with filtering/backwashing to kill the algae and dispell the white haziness.
I’m sure because I watched my son-in-law remove the filter lid via FaceTime. They cleaned the filter elements, reassembled the filter and put in half as much DE as usual (~3 lb.) since there is so much DE in the pool. My daughter brushed the pool immediately and within three hours the pressure went from 12 psi to 25 psi, so the algae-laden DE in the pool must have found its way back into the filter. The next day (today) the pressure was back down to 14 psi, so I thought the manifold must have jumped off the standpipe again. They dissembled the filter and found dark green DE on about 2/3 of the surface area of the filter elements. The rest of the element area had no DE on it, so I don’t know if the DE made its way back to the pool again but not sure how it did since the manifold was down on the standpipe.
I have two problems I have not seen much if any comment on any blog. I had tiny bubbles coming out the returns and thought it was DE going back into the pool. There were no leaks in the pipes by the pump and filter and I replaced and greased the pump basket o-ring. It turned out to be the Jandy valve next to the pump was full of leaves and sticks and air was getting into it. I removed the valve handle with cover, cleaned it out and replaced and lubed the o-ring. That fixed the bobble problem.
I have had DE and other small debris go back to the pool, which I normally discover when the screen in the Polaris hose where it connects to the pool wall gets clogged. Usually it is a torn filter grid(s) that DE is bypassing. Recently my daughter mistook DE that I had in a chlorine bucket for chlorine and she added several pounds of extra DE to the pool (instead of chlorine). (Poor training on my part). Sometime after she added it, the DE went back into the pool. She took the Pentair FNS60 filter apart and found the manifold was off the standpipe, so very little DE was on the filter elements because it had passed right back into the pool. This happened to me a few months ago and I found a small crack in the 2-inch female pipe part of the manifold where it fits over the standpipe. I replaced the manifold and the o-ring on the standpipe and it had a tight fit after putting the filter element assembly back into the filter.
Would the filter element assembly jump off the standpipe because there is too much DE in the filter and maybe the pressure was to high? This did not happen for 15 years and now has happened twice in six months.
That might be the cause. But are you sure she just didn’t bump hard when she took the filter lid off?
I have a Pantair FNS PLUS 60 with a Hayward DE separation tank C9002SEP and the filter seems to be fine , problem is when I backwash to the separation tank after about 20 seconds it shoots DE into my pool via return jets. No problem with DE during filter operation only on backwash. I contacted Haward and was told to replace the DE bad , witch I did , same problem. I have inspected spider gasket in my multi valve assembly and it seem to be fine, spring seem strong and only residue is in the waste port inside to multi valve.
Am confused and would appreciate any help.
Thanks
K.R
I presume, your multiport Valve’s waste port is piped directly to your separation tank, then the tank line from the separation tank is brought back to the return line? If that is the case then I do not see how DE could be getting back to the pool unless it was a bad spring or spider gasket.
You probably should have someone come out and take a look at it.
I find no evidence of DE in any other port when my MPV was open for inspection ,I did see a little DE in the waste port , but that makes sense. My pool pro looked at it with me and no sign of gasket problem and I would think i would see DE in another port if it was bypassing. Separation tank is piped waste to inlet and outlet goes to a tee which proceeds to the pool return line, i”ve been using this system for 5 years without a glitch. It starts about 20 seconds into backwash and not on filter setting. I”m very confused .
Thank you Matthew for your quick response and knowledge.
Any thoughts ?
thanks again
K.R
You might want to try asking this question in Inyo’s forum so you can post pictures of your plumbing. Because working blind while trying to fix a pipe issue is not the easiest thing to do.