I have combed through dozens of threads, but I cannot find anything that will resolve the issues I am having with my sand filter. I have an Intex Krystal Clear 28645EG sand filter and pump. I have checked the fittings to make sure they are secure. I have disassembled the pump to make sure it is clean and the impeller is spinning freely. The sand is only 1 year old, as is the filter and pump. When I run the pump, it progressively loses flow to the point where hardly anything exits the pump into the pool. There are no obstructions in the inlets or hoses. I can recover the flow by either running the recirculating or backwash functions on the filter. That will allow the flow to go back to "normal," but then the clock starts ticking until the flow decreases to almost nothing. What else can I check for this problem?
Pump Progressively Losing Flow
- Thread starter mkkarnold
- Start date
- May 3, 2014
- 59,354
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Welcome to the forum!
What does your pool water look like?
Can you post pool water chemistry test results?
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.
What does your pool water look like?
Can you post pool water chemistry test results?
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.
Oly
Gold Supporter
Sounds like your filter is loading up, you may have an algae bloom starting. Is your water clear? Water chemistry test results may explain this problem. How are you monitoring your water chemistry and sanitizing your pool?
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Your description is a textbook example of a dirty filter.
You get good flow on recirculate. That means it gets sucked into the pump, sent to the multiport valve on the filter, and then straight back to the pool. So good flow means no clogs in the skimmer or pump impeller, no air leaks, no collapsed hose.
That leaves only the filter. Low flow and high pressure indicate a dirty filter. You backwash and the flow improves. Diagnosis confirmed.
Now you need to look at WHY this is happening within hours rather than the usual weeks or months. Is the pool green? Is it cloudy?Does the water look dull?
Based on my experiences here for several years, I'll wager you have algae. It might not be bad enough to show up as green. Yet. You're probably at the equilibrium where you're killing it as fast as its growing, hence the endless supply of dead algae to clog your filter. One day without enough chlorine or a sudden heat wave and it's all over. It'll be green.
The cure is to kill the algae faster than it can reproduce until its all dead. We call it a SLAM Process It's not the same as "shocking" the pool the way the pool store teaches. I urge you to read the article. There are also plenty of threads with pictures here. Just do what they did.
You get good flow on recirculate. That means it gets sucked into the pump, sent to the multiport valve on the filter, and then straight back to the pool. So good flow means no clogs in the skimmer or pump impeller, no air leaks, no collapsed hose.
That leaves only the filter. Low flow and high pressure indicate a dirty filter. You backwash and the flow improves. Diagnosis confirmed.
Now you need to look at WHY this is happening within hours rather than the usual weeks or months. Is the pool green? Is it cloudy?Does the water look dull?
Based on my experiences here for several years, I'll wager you have algae. It might not be bad enough to show up as green. Yet. You're probably at the equilibrium where you're killing it as fast as its growing, hence the endless supply of dead algae to clog your filter. One day without enough chlorine or a sudden heat wave and it's all over. It'll be green.
The cure is to kill the algae faster than it can reproduce until its all dead. We call it a SLAM Process It's not the same as "shocking" the pool the way the pool store teaches. I urge you to read the article. There are also plenty of threads with pictures here. Just do what they did.
Ok, so that makes sense based on my situation. The chemical levels all test ok, except for stabilizer which I just added. It got a bit... nasty over the winter due to my negligence, so I am clearing out organic debris and dead algae. I used a bunch of algaecide to kill off the problems, now the junk on the bottom is slowly clearing each time I vacuum, but based on what you are saying, it sounds like when it gets stirred up into the water, it is clogging the filter possibly? So, I am assuming, until I clear that nonsense out of the pool completely, which I am very close to completing, I should just keep clearing the filter?
- May 3, 2014
- 59,354
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Algaecide does not kill algae.
You need to SLAM Process.
What are your test results and how are you testing?
You need to SLAM Process.
What are your test results and how are you testing?
Ok, here are my levels based on my test strip, which appear to confirm what you are saying:
Total chlorine - almost 1
Free chlorine - close to 0
PH - 7.1
Alkalinity - 110
Stabilizer - 40
Yes, the water is slightly green but very much improved from 1 week ago.
Total chlorine - almost 1
Free chlorine - close to 0
PH - 7.1
Alkalinity - 110
Stabilizer - 40
Yes, the water is slightly green but very much improved from 1 week ago.
- May 3, 2014
- 59,354
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Great. Test strips are not sufficient. To properly manage your pool water chemistry, and to follow the SLAM Process process, you need a proper test kit.
Order a TF-100. See Test Kits Compared
While waiting on delivery of your test kit, add 5 ppm FC worth of liquid chlorine/plain bleach to the pool water each evening.
Order a TF-100. See Test Kits Compared
While waiting on delivery of your test kit, add 5 ppm FC worth of liquid chlorine/plain bleach to the pool water each evening.
Oly
Gold Supporter
Yes this is the source of your issue. As the temps rise the algae is going to overrun your pool so you need to take control. The test strips are not accurate enough and are not helping you so gear up and take control. Once you have your water sanitized and balanced the maintenance is easy and there is no need for expensive chemical potions.
Awesome, I will work on getting that now. I had a feeling the strips were insufficient, so thanks for clearing that up. I have added the chlorine, and the test kit should be here tomorrow. Thanks!