Filter or Circulation Problem?

by Holly
(Greenville, SC)

When I opened my pool this year I started having a problem with the pool filter losing prime. I saw a spin fitting that was dripping so my son replaced the gasket in that fitting and that helped a little bit, but after running all day the water in the tank by the pump is down about an inch and not washing the lid and by the end of the 2nd day it is down to the top of that filter basket there and sluggish. I've cleared both filter baskets many times. If I backwash the pool that clears it up and it runs well again but I have to do that every 2 days.


There is also very little suction when I vacuum through the filter but if I vacuum to waste it works fine. Water was clear until a week ago and now it is cloudy and verging on an algae bloom. The pressure gauge is broken and I need to get it replaced.

One thing I have noticed is that when the pump is running it sounds like there are rocks or something rattling inside the top of the sand filter or where the handle is to change the setting. The handle turns easily though and there are no leaks.

I replaced that handle and gasket 2 years ago. I have checked the chemical levels morning and evening every day and adjusted as necessary. I shocked the pool this morning before I went to work just because it looked like it was on the verge of turning green even though the chlorine level was ok.

Tonight if anything, it looks greener. Using my Taylor test kit the Chlorine tonight was total chlorine of 5, Free chlorine of 10, Ph 7.2, Alkalinity 90 and stabilizer of around 100. Since the pool looks greenish and the free cholorine was below 12 I went ahead and shocked it again tonight.

I'll take a water sample to the pool supply place tomorrow for more accurate readings but I don't trust any advice they give me after the problems I had with chlorine lock due to stabilizer levels that were so high they couldn't even be measured 3 years ago and they kept telling me to add more stabilizer to the pool without even testing the stabilizer level! I'm not sure if currently I have a sand filter problem or an air leak.

I've called three local service companies to ask them to come look at it and while 2 called back, neither one wanted to come out and look at it. They both said based on what I told them that my sand is clogged and to run the filter 24/7 and keep backwashing and if it didn't get better to change out the sand and that I could do that myself.....

The sand was changed 3 years ago by a friend who is no longer available and the pool is lightly used just on the weekends. There is no sand in the pool so I don't think a lateral is broken. Opening filters and changing sand or determining if that is really the problem is an issue beyond what a 50+ female first time pool owner can handle.




Thanks for the question Holly

First thing I'd tell you is to stop shocking the pool and here's why. Your CYA is too high at 100ppm. Take a sample of pool water to your local pool store and compare the reading to yours. The Taylor kit I recommend is the K-2006 kit. I have several videos on YouTube that go into great detail on how to use it. You can start with the chlorine right here:

https://www.youtube.com/watch?v=ZZwZEGCMaZg

Next, you need to understand that there's a relationship between the free chlorine (FC) and the CYA. The FC level is 2 - 4ppm and the CYA is 30 - 50ppm. Your CYA is 7.5% of your FC.

This is an easy 3rd grade math equation. Say you run the chlorine at 2.5ppm, simply divide 2.5 by 7.5% and you get 33.

2.5 (FC) divided by 7.5% = 33

Now, as the CYA increases through Trichlor tabs the chlorine needs to increase as well. If you allow the CYA to get to 100ppm, you need to run the chlorine at 7 - 8ppm for the chlorine to be effective.

7 (FC) divided by 7.5% (CYA) = 93.

8 (FC) divided by 7.5% = 106.

When the CYA gets this high the only way to reduce it is a partial drain and refill. There's no chemical to reduce the CYA. Let's use common sense. If your CYA is at 100ppm, and the range is 30 - 50ppm, then by draining 1/2 of the water and refilling it you'll drop the CYA to 50ppm. You need to do a 2/3 drain and refill to reduce the CYA down to around 30ppm. Here are videos on that:

https://www.youtube.com/watch?v=5p79jZcdK6A
https://www.youtube.com/watch?v=ZEEzVlfNAYY
https://www.youtube.com/watch?v=Iau9CXWGtP0

Next is chlorine lock. You probably were told this by a pool store employee. There's no such thing as chlorine lock. This is a default answer from someone who wants a customer to think he knows what he's talking about. Here's a video on that:

https://www.youtube.com/watch?v=Ig62hN_ODBw

You will always get better suction vacuuming to WASTE because you bypass the filter. You may have a suction side issue. Here's a good troubleshooting video on that:

https://www.youtube.com/watch?v=ElMwJmGSIFc

I don't doubt you in the least when you way you were told to keep adding stabilizer even if they were not testing it. Again, my guess is that because your CYA is so high the FC is rendered very ineffective thus causing green pool water. Remember that green or cloudy water is a symptom of a problem, not the problem itself.

So to sum it up - Watch all the videos and do a 2/3 drain and refill, FILTER for 10 hours and allow the new water to mix with the old, retest and start making the adjustments.

Here's my page on a green pool I cleared up that's very similar to yours. The CYA was at 100ppm so drained and refilled it and within 7 days it was perfectly balanced and crystal clear. And all for about $32 in chemicals. Video series #1.

Green Pool Video

I hope this has answered your question to your satisfaction.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Sand Filters" category.

Check back to this post for updates or answers.

If you feel your situation is more complex and want immediate assistance (within 24 hrs) you can make a donation of your choice and I'll answer your questions by phone.

Have I helped you find a solution to your pool problems? Did this information help you? Please consider making a donation to help keep this site going. Thank you.









Have a great Summer.

Robert

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Skimmer Back Flow

by Brian
(Exeter ,Pa. USA )

When I shut off my jacuzzi above ground filter I get a rush of water back thru the skimmer and filter makes gurgling noises.

Pressure is at 12psi when running. I have back washed but that didn't help.

Any ideas?




Thanks for the question Brian

I have answered the same question here but will throw in a few more ideas:

Pool Strainer Overflows..Lid Blows Off..

The pool pump compresses the air in the filter. When the pump turns off the air will expand and push water out of the skimmer.

You need to check the pump lid O-ring for cracks or tears. If any are present you need to replace the O-ring. Make sure the skimmer basket is clean and the water is flowing without any vortex or burping.

There could be alot of pressure built up inside the lines or filter tank. Make sure all the valves that need to be open are open and the multiport valve is on FILTER or the proper position to allow water to return to the pool.

Be sure to bleed the filter using the bleeder valve to release any air inside the tank.

I hope this has answered your question to your satisfaction.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Sand Filters" category.

Check back to this post for updates or answers.

If you feel your situation is more complex and want immediate assistance (within 24 hrs) you can make a donation of your choice and I'll answer your questions by phone.

Have I helped you find a solution to your pool problems? Did this information help you? Please consider making a donation to help keep this site going. Thank you.









Have a great Summer.

Robert

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Return to Swimming Pool Sand Filters.

Pool Water Circulation In Reverse

I hooked up my pool and primed the pump as per directions and my system is cycling backwards, intake on the jet and discharge from the skimmer.

What the ? This pool is only 2 years old....




Thanks for the question

Normally when this happens it is caused by one or a combination of things.

First is the obvious. The system is plumbed backwards. The suction side is going to the return side.

2nd would be the multi-port valve. Have you worked on that recently? It may not be set correctly. Many new models have a notch on the base and the MPV that are matched up. These need to be in alignment.

If incorrectly installed, the filter can flow in reverse. Be sure the pump is connected to the port marked "pump" on the valve.

I hope this has answered your question to your satisfaction.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Sand Filters" category.

Check back to this post for updates or answers.

If you feel your situation is more complex and want immediate assistance (within 24 hrs) you can make a donation of your choice and I'll answer your questions by phone.

Have I helped you find a solution to your pool problems? Did this information help you? Please consider making a donation to help keep this site going. Thank you.









Have a great Summer.

Robert

Click here to read or post comments

Return to Swimming Pool Sand Filters.

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