No one has been able to resolve this issue!

jmar311

Member
Jun 17, 2016
10
tampa
Greetings everyone,

So I've been battling my pool issue for months. What seemed to be a relatively straightforward fix has turned out to be somewhat of a head scratcher.

Specs of pool:
-15,000 gal in-ground pool with adjoining spa
-Hayward Ecostar pump sp3400vsp
-Hayward Pro‑Grid DE3620 DE Filter
-Hayward SP740DE Selecta-Flo Multi Valve

The issue:
All the other 3 pump modes work with no issue at all and the pump primes and runs as expected. i.e. Circulate, Waste and Backwash. However, as soon as I turn it to Filter mode the the jets in the pool and spa on the return begin to decrease in pressure to the point after 10-15 mins the jets are trickling water back to the returns in the pool and spa to the point where it looks like the pool pump is not running (ie the swirls in the water surface). And when I put my hand up to the jets when i start Filter mode they are strong as expected but 15 mins later they are reduced to the pressure of a public drinking water fountain.

So first thing one would say is backwash and problem solved right? I do that and then same issue. Then they say well back wash again. I do that and the issue continues. Then various pool tech shave said well reduce your DE powder amount u add... I've done that many many times and issue still continues.

So knowing that we have the issue narrowed to the Filter mode and the water going through the filter techs have said well u will need to manually pull the grids, clean them, degrease them and then put them back in and your problem will resolved. I've done that probably 7-8 times and the problem still continues. Then the techs have said "hmmmmm, well you will just need to go buy new grids (even tho they were degreased and heavily pressure washed and u could eat off of them they were so clean) and then that will fix your issue". So I go buy new grids and put them in and surprise, surprise, same issue still occurs. So I don't see how it could be the grids themselves although common sense and logic would say it's the grids cuz that's what is straining the water flow and causing the return jets to lose so much pressure. I too agreed with techs and did all of the steps outlined above and have concluded it cannot be the grids.

So the only other question I have to you guys is could there be another point in the Filter mode, like the pipes or something im not aware of that could be killing the water flow and pressure to the return jets? Could there be a blockage or clogging somewhere else upstream or downstream from the Filter that is causing this?

This issue has me beyond frustrated because of how much work I've put into it with no results with countless solutions suggested. I know the issue seems minor but I literally cannot filter my pool cuz the filtration ceases to a trickle after 15 mins.

any help would greatly appreciated and I would deem anyone that can resolve this a frickin genius!!!

Thank you for listening!
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
32,618
Laughlin, NV
The one thing you never mentioned was pool water chemistry.
Can you post a full set of test results from your own test kit?
 

jark87

Silver Supporter
Jun 5, 2011
214
Flower Mound, TX
I had a similar issue a few years ago, although my filter would clog up after a day or 2, not within minutes. Even though water tests showed everything in balance, I suspect I had an algae bloom or some other contamination, like sap from the trees. I treated the water with Leslies Pool First Aid, which is probably not recommended on this forum, but it fixed my problem.

Best of luck getting it resolved!
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
34,278
Sebring, Florida
However, as soon as I turn it to Filter mode the the jets in the pool and spa on the return begin to decrease in pressure to the point after 10-15 mins the jets are trickling water
So, pretty easy to figure out, really. You have algae in your pool and it is rapidly clogging your filter causing your psi to go up and your flow to slow down to a trickle. We see that on the forum almost every day.

That why mknauss is asking you for test results. Your chlorine has been or still is inadequate and algae is in your pool.......whether you see it or not,

Eventually, you will have to SLAM your pool but before you can do that successfully you must do your own testing and get a kit that will allow you to complete the SLAM.

1. Please read "The "ABC's of Pool Water Chemistry" up in Pool School. Then read the SLAM article in Pool School

2. Order either the Taylor k-2006C or TF-100 test kit so you can take charge of your own pool. the TF-100 takes two days to get from NC to Tampa.

3. Once your kit gets in, please post a complete set of test results and we'll all help you get your pool clear.
 

jmar311

Member
Jun 17, 2016
10
tampa
So, pretty easy to figure out, really. You have algae in your pool and it is rapidly clogging your filter causing your psi to go up and your flow to slow down to a trickle. We see that on the forum almost every day.

That why mknauss is asking you for test results. Your chlorine has been or still is inadequate and algae is in your pool.......whether you see it or not,

Eventually, you will have to SLAM your pool but before you can do that successfully you must do your own testing and get a kit that will allow you to complete the SLAM.

1. Please read "The "ABC's of Pool Water Chemistry" up in Pool School. Then read the SLAM article in Pool School

2. Order either the Taylor k-2006C or TF-100 test kit so you can take charge of your own pool. the TF-100 takes two days to get from NC to Tampa.

3. Once your kit gets in, please post a complete set of test results and we'll all help you get your pool clear.
So, pretty easy to figure out, really. You have algae in your pool and it is rapidly clogging your filter causing your psi to go up and your flow to slow down to a trickle. We see that on the forum almost every day.

That why mknauss is asking you for test results. Your chlorine has been or still is inadequate and algae is in your pool.......whether you see it or not,

Eventually, you will have to SLAM your pool but before you can do that successfully you must do your own testing and get a kit that will allow you to complete the SLAM.

1. Please read "The "ABC's of Pool Water Chemistry" up in Pool School. Then read the SLAM article in Pool School

2. Order either the Taylor k-2006C or TF-100 test kit so you can take charge of your own pool. the TF-100 takes two days to get from NC to Tampa.

3. Once your kit gets in, please post a complete set of test results and we'll all help you get your pool clear.
Thanks Duraleigh for the response and suggestions. I get my water tested every week and within these months of the issue the water has been consistently balanced and the issue has continued. Thats why I didnt post the test results. Having done the solutions I listed above during the the time period with balanced water I just don't see how pool chemistry could be the issue if my water is balanced. I can post the test results that show its balanced but I think the issue goes beyond that as I've been at this for awhile. I have my own kit too that I can do the testing but it typically matches the water testing at the pool store.

I've slammed or shocked the pool many times even as additonal measure and that still has not resolved issue hence the reason I think it's something else. I would do it again but having done that multiple times as an additonal 'just in case' step I don't see what else that would yield in results. If I'm missing something please let me know.
 

jmar311

Member
Jun 17, 2016
10
tampa
I had a similar issue a few years ago, although my filter would clog up after a day or 2, not within minutes. Even though water tests showed everything in balance, I suspect I had an algae bloom or some other contamination, like sap from the trees. I treated the water with Leslies Pool First Aid, which is probably not recommended on this forum, but it fixed my problem.

Best of luck getting it resolved!
Thanks Jark87! I too think it's something clogged thats causing a major decrease in flow in Filter mode. I can try this product and see if that works but I definitley think it's something like this that is going on especially since u have experienced the same thing. I'll let you know how it goes after I use this product. Thanks.
 

Newdude

Well-known member
Jun 16, 2019
4,441
NY
I too think it's something clogged thats causing a major decrease in flow in Filter mode
You cleaned, Deep cleaned and then replaced all the guts of your filter, Yet it continues to clog. Your filter is doing it’s job perfectly and is clogging up with the algae bloom that your eyes cannot see yet. You very well may be keeping the bloom right on the edge before it explodes into a green swamp, but it IS there.

you mention having your water tested and also completing a SLAM. You cannot successfully SLAM without your own, reliable, test kit. If you had actually performed a proper SLAM and passed it, You would not have gone all these rounds back and forth. We never need to ‘shock’ here.

It’s ok. The pool store has fooled millions before you and will continue with millions more after.

So your choices are to learn how to take control of your pool. (Cheap, easy and effective), or keep doing what you’ve been doing. Not for nothing but what you’ve been doing hasn’t helped.
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
34,278
Sebring, Florida
Every response you have received has indicated they think you have algae. Those respondents have somewhere around 68,000 posts on this forum going back over the last 15 years or so. It's up to you to give a try to what we suggest.......it's your pool
 

jark87

Silver Supporter
Jun 5, 2011
214
Flower Mound, TX
Thanks Jark87! I too think it's something clogged thats causing a major decrease in flow in Filter mode. I can try this product and see if that works but I definitley think it's something like this that is going on especially since u have experienced the same thing. I'll let you know how it goes after I use this product. Thanks.
I agree with the others regarding pool store tests. I use the Taylor K-2006. Leslies has been very helpful to me on a number of issues, but there always seems to be some variability in their test results vs. mine. I wasn’t familiar with the TFP SLAM process at the time of my issue. I’m grateful that the Leslies product worked and hope it also works for you, but I’ve gained a real appreciation for understanding my own test results instead of blindly following Leslies recommendations. For example, just today, they showed my Alkalinity at 55, when my test showed 70. They recommended 16 lbs of alkalinity increaser, as they also recommend a range of 80-120 vs the 60-80 that I’ve follow for 13 years. I came home, tested again, and confirmed my own results. Not sure what the result of 16 lbs of alkalinity increaser would have been, but I’m glad not to be dealing with it!