pool loses suction

[aspen26]

I have the cursed pool... 4 years and I'm my 3rd set of pumps and filters and still no clean pool.... my suction isn't the greatest but it gets to be almost obsolete after running filter for an hour or two.... I just replaced the pump with a new 1.5 horsepower pump and just change the sand in my filter and I'm still having issues.While changing the sand I noticed broken laterals. I had my other filter still that was barely used so I replaced my standpipe and laterals with the other ones. The filters were not the same size or brand but they are in good condition because that filter sprung a leak shortly after purchase. Would that be causing problems???? I have changed the PVC pipe three times to be sure there are no leaks..... the pool has great pressure when it's running on recirculate... when it's on filter it runs for a while and then loses pressure so I backwash and rinse and then it regains its pressure... but slowly loses it again. my multiport valve is a little troublesome but would that cause priming issues??
I'm at a loss at this point... I don't know what to do....
is it the laterals or the multiport valve?? should I replace the filter?? or is it something else ??

 

[Texas Splash]

Welcome to TFP! What you are describing sounds suspiciously like a chemistry issue not mechanical. I feel you may have an algae outbreak in-progress. To confirm, we would need to see a full set of water test results. Can you provide those please?

FC
CC
CYA
PH
TA
CH

ABCs of Pool Water Chemistry

 

[Brett S]

What is the condition of the water? If the water is green and/or cloudy, then it sounds like the filter is doing exactly what it’s supposed to be doing... pulling stuff out of the water. The more stuff the filter pulls out of the water the harder it is for the pump to push water through the filter and the flow rate will decrease. Once you backwash the filter it will be clean again and have a good flow rate, until more stuff gets caught in the filter.

If the pool water is particularly dirty and/or the filter is undersized then it’s quite possible for this to happen in a very short time frame. In addition to the test results requested above can you provide the size of your pool and also the size of the filter?

 

[aspen26]

the pool does have algae ... I just drained it partially and scrubbed the walls and such and after refilling I found out I needed a new pump so the pool sat for a little over a week before I could deal with it again.... then for the following 2-3 weeks I started working on the chemicals but nothing was progressing .i started to notice that the pump didn't seem to be priming. called pool store and they suggestee i change the sand ....
I'm just at the point now that I'm scared to run the pump too long because I have already burnt up other pumps ...
also I read that I shouldn't drain above ground pool completely.... would it help if i did and started with fresh clear water .??
I have an 18x30 oval above ground ... wi th 1.5 Hayward pump and 24in astral millennium filter

 

[Texas Splash]

the pool does have algae ...

That's what I suspected and good to know. So what's happening is the algae is actually clogging-up your filter quickly, causing a restriction in water flow, and effecting your prime and circulation. I doubt you have any mechanical problem, it's all about chemistry now. To kill and remove algae, you need to follow what we call a SLAM Process. It's not an overnight process and can take several days, but it works. To perform a SLAM you also need to have the proper test kit. The TF-100 (or Taylor K-2006C) are ideal for this purpose. But you need one or the other. See Test Kits Compared.

The one unique challenge I see today is having enough chlorine or regular bleach. That is the weapon of choice for the SLAM Process. Since a SLAM can take several days or perhaps a week or more depending on the amount of algae, you'll need several gallons throughout the SLAM. If bleach is in shortage at your location, you may have to exchange more water just to try and get ahead of this thing. You should be able to lower the water down to about 18 inches or so. You'll still need to do the SLAM for the remaining algae and filter material, but it may help.

But the proper test kit and SLAM are the way to go. Look-over those links and let us know if you have more questions. Have a good day.

 

[aspen26]

when I changed the laterals for my 24in filter we used the laterals from my 20in hayward..... does it matter if they aren't the same laterals they came with, or the same size for that matter?? I'm worried that because I didn't get the lats that match the filter that nothing I do will work anyways....and i also have no information on the filter I have now so I did research to try and figure out how much sand to put in it because I have no clue what it calls for...

 

[aspen26]

also ... after changing all the sand and laterals my multiport valve just broke so I can barely turn it... so I don't even know if changing the sand and laterals worked....

I had a lot of trouble with one of the orings on my unions staying put ... I pretty much lubed it and forced it in and quickly closed the union... it ended up leaking so I did it again with Teflon tape... now it's not leaking . ... but could this cause priming issues.....??

 

[Texas Splash]

Sounds like you are really having a tough time. Not sure about the laterals' impact on the water flow and filtration. Might depend on the difference between the original and replacement sizes. But I don't think that's adding to the algae issue. That's all about chemistry. So the proper test kit noted above is very important. As for the multiport valve, I hope you are able to get that resolved soon. Good luck and keep us posted if you have more questions.