Problem: locations around pool has sand-like dirt collection

[cflannagan]

We used to have weekly pool service, but have stopped it in November and begun doing everything DIY. We make weekly visits to local Pinch-A-Penny with our pool water sample to have it tested, and buy whatever is recommended.

Tried opening up our filter system to do the annual cleaning but to no avail - just could not open it up because some of the knobs around side would not loosen no matter how hard I try to loosen them.

Hired pool service for one-time visit to assist and educate me a bit more about cleaning our filter system. Had to use big monkey wrench to loosen up some of the knobs around the filter system, and finally got it opened. The set of filter grids were very dirty (thick with dirt/stuff), we hosed it off. However, there is a hole in one of the filter grids, and the guy said we will have problems in coming weeks because of that hole, and he was right.

He also could not even, with a monkey wrench, loosen the filter grid set to remove it. He mentioned that a new filter-grid set would cost me somewhere around $180, and because the filter system is old, and difficult to maintain, that I probably should consider buying a new filter system that is easier to maintain for a DIYer - he mentioned "Clean and Clear 150" for $525. Unless advice from this forum tells us otherwise, we are definitely are considering buying a new filter system as long as it is the right choice.

However we have an immediate problem - there are regions around pool that has sand-like collection, and for some reason they don't go away, even with our automatic pool cleaner doing it works. I suspect that the debris is simply returning back to our pool back from the filter system, because of that hole in one of the filter grids. Just did not expect it to happen as quickly or bad as it did.

What would be the best/easiest way to remove sand-like dirt from our pool? A new pool canister with filter bag with low micron rating (can catch fine particles), or buy a wand cleaner and do some spot-cleanups? We live in Florida, and our pool is inside a lanai ("florida room"), so most of the time when debris enters our pool, it is simply just a bit of dirt or sand off the sides of our pool (we have patio around our pool).

We are in process of replacing our filter system very soon (with a month), we want to make sure we do diligent research before making our decision on whether our filter system truly need replacing and with what new system.

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

Showing pixs of our problem

 

[zea3]

Re: Problem: locations around pool has sand-like dirt collec

Hi! Welcome to TFP! Can you post a set of current test results? I don't think it is algae but it helps to have that info while we are brainstorming your problem. How big was the hole in the grids? Can you set the pool to recirculate (by pass the filter)? Do you get a lot of dirt blown into the pool area?

 

[JamesW]

Re: Problem: locations around pool has sand-like dirt collec

Have you felt the sand like stuff? Unless it's actually sand, then I think that it is probably mustard or brown algae.

You need to fix the filter and bring the chlorine up to shock level until the algae is all killed and removed.

A full set of test results will help

FC
CC
pH
TA
Calcium
Cyanuric acid
temperature

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

Just took an Aqua Chem 6-way strip test

Total Hardness: about 250
Total Chlorine: color falls between 3 (OK) to 10 (HIGH), but based on tone, definitely closer to the 3 end
Free Chlorine: again, between 3 (OK) to 10 (HIGH) but definitely closer to 3 end
pH : between 7.2 to 7.8
total alkalinity: about 120
total stabilizer: between 50-100

I'm not really sure it's any type of algae, as the particles floats freely back up off the bottom if you disturb the water near them (like swiping at them but not touching them). The color is almost black, which I think rules out mustard algae.

 

[JamesW]

Re: Problem: locations around pool has sand-like dirt collec

I'm pretty sure that it's algae. The first thing you NEED is a good FAS-DPD test kit such as the Taylor K-2006 or the TF-100. Right now, you should raise the chlorine to about 20 ppm using liquid chlorine or regular unscented bleach (6 % sodium hypochlorite).

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

Update:

Found results done by our local Pinch-A-Penny store. As mentioned in original post, we talk water samples to local Pinch-A-Penny on weekly basis and they print out results for us, and we file those result print-outs, and we treat our pool on a weekly basis. Here's the results from yesterday, my wife said she applied alkalinity increaser this morning (9.8 pounds total, which was what store gave her).

Photo attached.

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

I'm pretty sure that it's algae. The first thing you NEED is a good FAS-DPD test kit such as the Taylor K-2006 or the TF-100. Right now, you should raise the chlorine to about 20 ppm using liquid chlorine or regular unscented bleach (6 % sodium hypochlorite).

How do we confirm that it's algae and not just dirt returning to our pool because of a torn filter grid in our system? I'd feel better if we have some way of confirming that it's really algae before taking action; I just did a bit of read-up on mustard algae, and literature says they have yellow-to-dark-yellow color, which is definitely not the color of the particles floating around in our pool.

 

[zea3]

Re: Problem: locations around pool has sand-like dirt collec

Conventional pool store wisdom does not take the CYA level into account when determining what level FC should be. 4 is too low for a pool with a CYA of 80. I plugged your information into The Pool Calculator and you should be maintaining a FC level of 6-11 to sanitize your water.

To determine if the dirt is coming through your filter, hold a clean white sock over the return to catch some of the material next time you vacuum. See if you can collect some of the dirt from the shallow end. Algae will have a slimy feel to it. You can get some on your finger and smear it on a white sheet of paper and see if it leaves a mark.

 

[JamesW]

Re: Problem: locations around pool has sand-like dirt collec

Fix the filter and vacuum out all of the debris. If this solves the problem then you are done.

However, I really think that you have an algae problem. If you don't get some chlorine in there fast, then it's only going to get worse. Shocking won't hurt anything.

What type of chlorine do you use? I'm going to guess that you use chlorine tabs in a feeder or floater? The tabs add stabilizer. 80 ppm is at the top of the range, and only for SWG pools. You need to stop using tabs and switch to liquid chlorine.

Your chlorine levels are not adequate for the stabilizer (cyanuric acid) level. That is what has allowed algae to get started. Mustard algae is particularly difficult to treat, especially with elevated levels of cyanuric acid.

You might have to do a partial drain and refill to lower the cyanuric acid level to be able to defeat this algae. Start out by raising the chlorine to 30 ppm and keep it there until all of the algae is gone.

You can't do a proper job without being able to accurately measure the FC at up to 50 ppm. You need FAS-DPD to do this.

 

[zea3]

Re: Problem: locations around pool has sand-like dirt collec

Just thought of something. Do you have a lot of trees in your yard? How closed is your pool enclosure?

 

[Bama Rambler]

Re: Problem: locations around pool has sand-like dirt collec

Don't get all stressed out and think you have to run out and buy a new filter and a bunch of other stuff right now! A few days spent here while we figure this out is fine.

That stuff looks just like the oak worms (blooms) that have broken apart and settle in the bottom of my pool, which is definitely NOT algae. I agree that your filter is a little problem but you can break it down and super glue a piece of plastic over the hole to limp by till you get a new filter. At least that'll let you figure out if it's filter related.

You really should consider getting a good test kit. It's well worth the money and gives you good numbers so you cna tell if what you're seeing is algae or not.

 

[JamesW]

Re: Problem: locations around pool has sand-like dirt collec

In the pictures, I see a greenish/yellow tint, especially on the walls, which looks like mustard algae to me. The darker "sand-like" stuff does not look like typical algae. It's probably a mixture of DE, dirt and algae.

I think that you should fix the filter, vacuum the pool to waste, brush daily and begin bringing the chlorine up.

You should also test for metals in case you decide to shock. High metals could stain if you shock.

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

In the pictures, I see a greenish/yellow tint, especially on the walls, which looks like mustard algae to me. The darker "sand-like" stuff does not look like typical algae. It's probably a mixture of DE, dirt and algae.

I think that you should fix the filter, vacuum the pool to waste, brush daily and begin bringing the chlorine up.

You should also test for metals in case you decide to shock. High metals could stain if you shock.

Another thing that leads me to think it is not algae: wife went to a birthday party two towns over and they had the same type of disorder in their pool (their pool is in an enclosure as well). I really think it is just outside factors (ie: type of trees that grow around here). There is nothing that feels "slimy" to the touch around pool.

The greenish/yellow staining you see is already there before this problem begun - the staining was there when we bought the house in November 2009. The surface is really, really old (at least 10 years old) and nearing end of its life and we are discussing about the next plaster job.

JamesW, and also per zea3's suggestion, we will definitely try to bring our chlorine levels up. I really like zea3's idea of testing with a white sock, so simple and this will help reduce my stress of not knowing whether or not the dirt truly is returning to pool from the filter system. I've actually been in pool myself vacuuming up those collections, and a hour later there seem to be more collections to vacuum up. I'd be surprised if there are algae that forms that quickly (within a hour)

 

[JamesW]

Re: Problem: locations around pool has sand-like dirt collec

It would help if you could vacuum to waste instead of through the filter. You should test for iron and copper.

 

[learthur]

Re: Problem: locations around pool has sand-like dirt collec

If/when you purchase a new filter (not a priority now) and assuming you want a cartridge model, do buy the largest mod you can afford. Not the small model you mentioned earlier.

As for now, catch some of the sand/algae and place on a papertowel and let it dry over night. Algae will become flaky like aquarium fish food. Sand will feel grainy and tree/plant parts will be crunchy like Grapenuts.

You should put those 6 way test strips in the trash. Those things are so inaccurate you will never get the chemistry correct using them. They are convenient, but doesn't matter since you can't balance your pool with them.

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

It would help if you could vacuum to waste instead of through the filter. You should test for iron and copper.

Right - the futile vacuuming I was attempting was before I created this thread. Which was why I was asking about alternative ways to remove the debris so it does not go through filter system (to recap: my question from the original post was

"What would be the best/easiest way to remove sand-like dirt from our pool? A new pool canister with filter bag with low micron rating (can catch fine particles), or buy a wand cleaner and do some spot-cleanups?"

To which I'm still not sure yet. But here's my plan of attack:

1) Increase chlorine levels in our pool to levels appropriate for our CYA level which is 80
2) Do a white-sock test to see whether or not particles is truly returning to pool thru the filter system
3) Figure out some way to fix that hole in one of the filter grids ("bandaid solution")
4) Invest into buying a good test kit (I'm thinking of TFT-100)
5) Remove those ugly collections around the pool somehow without having it go through the filter system (if #2 above does indicate it is a problem)
6) Anything else I also need to do according to pool calculator

 

[Bama Rambler]

Re: Problem: locations around pool has sand-like dirt collec

That looks like a good plan of attack.

I'd move #4 to #2 but that's just me!

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

We were able to confirm that we truly do have filtering issue!

Here's what the inside of clean white sock look like after attaching it to return for about 5 mins:

 

[cflannagan]

Re: Problem: locations around pool has sand-like dirt collec

Update:

Removed large collections via new spa wand that we bought today, to remove as much as we can from the circulation. Of course, doesn't take care of all dirt. We need spa wand anyway to do spot-cleaning if we need to from time to time.

Ordered TFT-100 kit online, USPS Priority mail.

Will be pouring in about 1.5 gallons of liquid chlorine in the eveningtime (when sunlight isn't so direct) so newly added chlorine won't break down immediately - we will make sure pool system is running at this time so everything goes through circulation.

Probably going to open up the filter system today, and figure out how I can plug that problematic hole in one of the filter grids so that the debris would quit returning to our pool. We have guests coming on Thursday and am hoping by that time to remove nearly all of the debris currently in our pool.