The last two years we have had problems with sand in the pool. We have 16x32 oval AG with Hayward pump/sand filter, 4-6 feet depth. We have literally taken the sand out of the filter twice, the last time 4 days ago. Inspected all laterals, pipe, all looked good. Then proceeded to take apart multi-port valve to check the spider gasket, lubed with magic lube but looked pretty good for 8-yr-old pool. I cannot figure it out. Granted, we have been shocking pool last couple days for some algae, so we’re SLAMing and haven’t vacuumed yet. But each time we vacuumed/backwashed last year, the sand would then generally return next time the filter was on. What’s weird is sometimes last season, just brushing the pool and then turning off pump before bed, there would be no sand in the morning! It’s driving me crazy we can’t figure this out. Hoping once we get it vacuumed/backwashed this year for the first time maybe it’ll be better....but already just by having run the pump last 2 days it seems problem is as bad as ever. Help!
Sand all over bottom of pool?
- Thread starter Jamie A 14
- Start date
Are you actually sure its sand and not dead algae? Can you pick it up and feel it?
Maddie
Maddie
Agree with above poster. Check to see if it’s actual sand, pollen, or algae. Pool filter sand is very coarse. It’s not like play sand as it has to have the jagged edges and imperfections to filter the water.
If it is actual pool filter sand, the most common issue is a broken lateral or oversized pool pump in comparison to your filter.
Also, I had a problem a few seasons ago with mustard algae. Mustard algae looks like dark sand, and it is very slimy between your fingers. If you brush it, it poofs up in the water. It will pass right through your sand filter. You will vacuum it up, only to find that it has returned the next day.
For weeks I thought it was dead algae, as it would not go away with normal SLAM’ing routine. There is a special process for getting rid of mustard algae, and it’s outlined in Pool School. Essentially, if it is mustard algae, you will have to elevate your FC to mustard algae levels and maintain until it’s erradicated.
If it is actual pool filter sand, the most common issue is a broken lateral or oversized pool pump in comparison to your filter.
Also, I had a problem a few seasons ago with mustard algae. Mustard algae looks like dark sand, and it is very slimy between your fingers. If you brush it, it poofs up in the water. It will pass right through your sand filter. You will vacuum it up, only to find that it has returned the next day.
For weeks I thought it was dead algae, as it would not go away with normal SLAM’ing routine. There is a special process for getting rid of mustard algae, and it’s outlined in Pool School. Essentially, if it is mustard algae, you will have to elevate your FC to mustard algae levels and maintain until it’s erradicated.
I can’t feel it right now, as it’s too cold, it’s on the bottom, and I’m not getting in?. But, yes it does cloud up when brushing and is darker. I did wonder about it being dead algae. This does make sense that it could be mustard algae. I will read up on this, thanks!
- May 3, 2014
- 62,625
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
It is most likely just run of the mill algae. Mustard algae is quite unique and unusual.
You need to SLAM Process. Read the article, get out your test kit (what do you have?), and start adding liquid chlorine.
You need to SLAM Process. Read the article, get out your test kit (what do you have?), and start adding liquid chlorine.
I have the fancy Taylor kit, have for several years, and we have been SLAMing. We’re looking good, water wise and levels too. Just the black junk at the bottom. But I plan to vacuum later today (busy weekend and haven’t had a chance). I am hoping it’s just dead regular algae.
Highly likely that it is just algae. How much chlorine are you adding each day?
Post up a full set of test results please
pH
FC
CC
CH
TA
CYA
Post up a full set of test results please
pH
FC
CC
CH
TA
CYA
I started the SLAM 3 days ago, with 3.5 gals 12% chlorine. Water cleared quickly, Since then according to tests I am adding about 1/2-3/4 gal per day. Last night passed the OCLT with reading of 17 FC. But I vacuumed, added water, and tested this afternoon and got a reading of 10. I added a gallon (probably more than I needed to) and just tested at 10pm and FC was 22
Additionally, after vacuuming (to waste), I checked about 2 hrs later and a lot of accumulation had settled on the bottom. I am sure it’s stuff that was stirred up and resettled. So, hoping if I just keep at the vacuum and brushing over the next couple days it will take care of it. I am hoping it’s only regular algae....how will I know if it’s more, like mustard algae?
Forget about mustard for now. Since you still have the dark stuff resettling, the SLAM process needs to continue. It is the chlorine that will fix the issue. Vacuum & brush will help, but that alone is not the cure.
While you need to test the FC at night and morning to know if you need to add chlorine, it is a moot point to do a OCLT. The water isn't "clear" yet. So the SLAM process continues until the dark stuff stops showing up.
Argh, so I tested FC this morning, it was 17. Pool as expected had some debris on the bottom, after having been vacuumed last night (resettlement from what was stirred up). I thought it looked about right, and brushed the pool, trying to move the debris to one area to be vacuumed later. Ran the pump for about 3 hrs, went to look, and debris alllll over again. I almost think it gas to be sand. I actually saw a few grains sitting on top of the pool light. I am beyond aggravated, as we have done everything to check things that would possibly be causing it. Will try and attach a pic. Suggestions???
Attachments
- May 3, 2014
- 62,625
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Have you removed the light to see if there is algae in the niche?
When you brush the debris, does it swirl up into the pool water (algae) or does it seem to slide across the pool floor.....much like dirt being swept on the kitchen floor
At least nine out of ten, if not more, are algae problems.
Can you post a complete set of test results so we can get a better "picture" of your pool?
At least nine out of ten, if not more, are algae problems.
Can you post a complete set of test results so we can get a better "picture" of your pool?
Yes it clouds up. Not like dirt being pushed across the floor. My test results from yesterday are in an above reply.
No, but I planned to do that today (but it’s soo cold her in Michigan today?)
@Jamie A 14 , the problem you are having is likely from algae. This black stuff will continue until the SLAM process is complete and no matter how much you brush or vacuum, that alone isn't going to make it go away. Maintaining FC at SLAM level per the FC/CYA Levels is needed as well. The black stuff will become less and less each day until it stops. Take a deep breath and let the process do it's thing. Unfortunately, it just takes a few days to work. Run pump 24/7 while doing the SLAM process.
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Based on reports (and your description) on the forum for the past 12 years or so...........99% chance it's dead algae.
If you posted CYA, I overlooked it. What was it?
I can't tell for sure but I get an underlying current that you are not being as aggressive as you need to be. That aggression DOES NOT include a massive overdose of Clorox but it does include......running your pump 24/7. As soon as you see enough debris on the floor of your pool, brush it up into the pool water.....let your filter take it in and then backwash as necessary. Vacuum when you can. Brush again. Keep your FC at SLAM value.
You must do all these things at once to vigorously go after the algae in your pool.......killing it with Cloroc and then getting your pool crystal clear with brushing, vacuuming, backwashing as necessary and running the pump 24/7.
If you posted CYA, I overlooked it. What was it?
I can't tell for sure but I get an underlying current that you are not being as aggressive as you need to be. That aggression DOES NOT include a massive overdose of Clorox but it does include......running your pump 24/7. As soon as you see enough debris on the floor of your pool, brush it up into the pool water.....let your filter take it in and then backwash as necessary. Vacuum when you can. Brush again. Keep your FC at SLAM value.
You must do all these things at once to vigorously go after the algae in your pool.......killing it with Cloroc and then getting your pool crystal clear with brushing, vacuuming, backwashing as necessary and running the pump 24/7.
Ok, I am on it! Problem is hubby doesn’t like pol on 24/7. He doesn’t do any if the pool maintenance ?. But I got it! I just went out and tested FC, was at 12 (2:00 p) after testing at 17 (8:30a). So there is chlorine loss , and algae. I removed pool light (algae spotted). So, added 68 oz 12% chlorine, brushed, and have filter running. We’ll see how it goes! Btw, CYA 40.