New Pool Owner-can't get debris out of pool

[Pam129]

Hi All,

We purchased a home 3 years ago with an in ground pool, 20 x 40 holds 45,000 gal. All of our levels are good and water is crystal clear. Hayward sand filter was replaced when we moved in, vinyl liner. We vacuum the pool on filter or waste, and the pool is clear after vacuuming. We backwash when needed. At night when pump shuts off and in the morning, the water remains clear with no debris. Once the filter turns on, within a few hours excessive debris is built up on the floors and walls. Not sure why this is happening, had many pool contractors out and some said it is normal, others are guessing the laterals. We have spent a lot of money trying to solve this problem-is it algae, dirt, the filter? Any ideas would be greatly appreciated!! See attached pictures

 

[PAGirl]

Welcome! I would guess it's algae that you are just slightly keeping ahead of. To know for sure, you would need a quality test kit that measures accurately. These are the ones recommended here, as they can measure higher chlorine levels. TFTestkits.net


You'll need to do a little bit of reading to understand how the process works. Pool School - ABCs of Pool Water Chemistry

Pool School - Read This BEFORE You Post


Once you get your test kit, you would do an Pool School - Perform the Overnight FC Loss Test (OCLT) which would tell you if you are losing FC to organics, such as algae. If you use tablets and powdered shock frequently, your CYA may be high.

 

[YippeeSkippy]

Hiya Pam, I hope we can help you figure this out

Can you pick it up? Does it feel slimy or gritty?

You have a sand filter, right?? Has anyone removed the sand and checked those laterals, then put the sand back in?

 

[Pam129]

Hi,

thanks for the info. We will have to try the test kit. You can't pick it up because even when we try to go to examine it (slowly as possible), it begins to disperse into the water. We don't shock regularly because we have the automatic chlorinator, and according to our test strips the levels are where they need to be. Will check exact levels today and post the results.

Our next step was to empty the sand and inspect the laterals. We were thinking of doing this ourselves as the companies we spoke to wanted $300+ to do this.

It is a crazy problem that no one can seem to figure out.

 

[PAGirl]

If it disperses easily, it's probably algae. Teat strips are notoriously inaccurate, a good test kit is needed.
You can easily perform a deep clean, rather than change out the sand. I will post a link when I get to my desktop.

 

[Pam129]

Thanks! That would be very helpful. We usually go to the pool store to get the water tested in addition to our strips. Maybe we should get our own kit as well. Went to pool store today, the guy said our levels are right on target. He also said that it can be sand because when the sand gets ground up and very fine it starts to look muddy and dispersed into the water (I'm not so sure though). He is also convinced it's not algae because it moves easily into the water (almost like a dust) and isn't green in color (not sure about this either bc Ive read that algae isn't always sticky and stubborn).

 

[JesseSchmidt]

Here's the link for Deep Cleaning a Sand Filter.

 

[triptyx]

You'll rapidly find three things about pool stores:
1. They don't understand the TFP methodology. They're taught using decades old science that doesn't work, specifically the relationship between CYA and Free Chlorine - they believe that there isn't really any relationship between the two. Hence, the pool store will tell you that your levels are "fine", when in reality they want your FC between 2 and 4, and your CYA between 30 and 150. We know from experience and science here that you must keep your FC at a level that is appropriate for the amount of CYA in the water. Pool School - Chlorine / CYA Chart
2. They usually want to sell you something, whether or not it will help you (newsflash - it usually makes things worse). In this case, I'm surprised they didn't try to sell you half the store. You lucked out on that one!
3. Their testing methods are terrible. Be it bad training, bad equipment, or just ignorance, you'll often find three different tests of the same water will give you three different results. This is why we want you to have your own, proper test kit. If you do your own testing, you can discuss your results with us and we'll be able to help you to lick your problem.

So, the decision you need to make is either to do the TFP method, OR the pool store. The two really don't work together at all.

 

[YippeeSkippy]

There is nothing in the sand filter equipment that would "grind up the sand" as the pool store employee suggested. Why he would think that is beyond me.

 

[triptyx]

There is nothing in the sand filter equipment that would "grind up the sand" as the pool store employee suggested. Why he would think that is beyond me.

Because he can sell you a bunch of pool sand to replace that bad, worn down, old sand you have in there right now of course!

 

[Pam129]

Hi all,

We did the over night free chlorine test. The level did not drop, and we tested it at night and again this morning around 8am.

 

[PAGirl]

Did you use the strips to do it?

 

[Pam129]

No we used a kit that tests chlorine, free chlorine, ph, alkalinity, cya, and a few other things. When we tested the fc at night it came up at 4, and in the morning it was the same. On the kit it said 3 is where we should be, so are we too high?

 

[triptyx]

Pam, please post a full set of results for all of the tests in your kit. Correct FC level depends entirely on the CYA reading.

 

[cj3737]

There is nothing in the sand filter equipment that would "grind up the sand" as the pool store employee suggested. Why he would think that is beyond me.

Just wow.... That guy has definitely never seen how a sand filter works... Willing to bet he will also predict that most of the debris in a pool comes from a hose...