Trouble with SLAM of neglected swampy pool, very cloudy

[bc1080]

Hi everyone!
We’re 1st time pool owners that bought into an algae filled/swamped pool that the previous owners seemed to have abandoned at the end of last season. It’s a 20’x40’ with 8’ deep end, records say 28k gals (but it could be a little more). It’s a salt water setup, but it was recommended to SLAM and treat it like a chlorine pool until it’s better stabilized. I have the pump running 24/7 for now.

I have been trying to SLAM the pool and hit a wall after some initial progress, I'm about 2 weeks in now. Original testing showed 0 chlorine, 0 salt, low alkalinity, and 0 CYA. The first day I added 5 lbs of shock and some algaecide (“severe treatment” level), and the green color mostly left the water by the next day but the pool has remained very cloudy since then. The first backwash was dark green, but since then they’ve been mostly milky white looking. I have been adding 1-2lbs of shock nearly every day just to try to keep up the FC levels. I also added some CYA after the first week to try to reduce losing so much FC to sunlight and if I am reading the test right it’s now around 30, that seemed to help a bit.

The main problem is that the water remains cloudy enough that I cannot see where to brush and vacuum below the first couple feet of water. I have made several attempts to brush/vac, but other than right around the water line I am mostly working blind and trying to follow a pattern. There was some junk coming out when vacuumed to waste, but not much compared to how much I was vacuuming (hard to get a good pattern due to the slope). I have also run a net with scooper across the bottom and gotten some nasty black-green organics occasionally at random from the deep end. But I don’t know how to do better right now because I can’t see down there. The water has just cleared up enough that I can start to see about 2.5-3 feet down, I tried to attach a pic of the haziness. I am not sure what else to do right now and am definitely open to suggestions or if I maybe need to go after a more specialty treatment.

Current tests per TF100 kit:
8.5 FC (this was a while after last addition)
.5 CC
30 CYA
pH appears in range, maybe on low end (not sure if test is accurate right now, it was slightly high before I did anything)
60 Alkalinity
125 Calcium hardness

 

[mknauss]

Follow the SLAM Process

 

[bc1080]

Follow the SLAM Process

Hi, I should have provided more background on my methods. I have been researching on this site for a while and have learned a boat-load, and have been trying to follow the SLAM process per that guide. I think I have replicated it fairly well using the information there and the pool math app. I forgot to say I did add CYA before starting the SLAM, but it only leveled out to around 20 at first and I increased to 30 later on. I've read lots of threads about it but every problem seems a little different.

While SLAMing, the appearance of the water should improve each day, though perhaps only by a little. If you fail to see any improvement you might have a problem with your filter, or have a higher CYA level than you think, or bad circulation, or have some other more complex problem

This is basically where I am stuck I think. I can't get to the completion criteria and don't really seem to be improving, at least the cloudiness doesn't seem to be going away at day 15.
At this point I'm basically testing and adding chlorine, netting whatever I can off the surface/upper water, trying bottom "scoops"/vacs to see if I get lucky and get anything, cleaning strainer, and backwashing when the filter PSI gets high enough. I have done 4 backwashes since starting the SLAM.

I admit that the FC was probably falling a bit low at times during the first week when the CYA was lower (had a lot of sunny days and the water was really dirty then), which I read can drag it out a bit.
Friends and neighbors have tried giving advice such as using clarifiers, use phosphate remover, etc... but I don't know if that is just a guess or at what point I need to be concerned or try something different.

 

[V___25]

Have you used any clarifiers or flocs? That stuff can mess up a sand filter if not vacuumed to waste. Maybe a deep cleaning of the sand is needed so it's not working very efficiently? Sand filters are notoriously slow but it might not hurt to take a look inside your filter and see what's going on in there.

 

[Lilypad]

I have been adding 1-2lbs of shock nearly every day

Use liquid chlorine and re-read the SLAM process. You need to be testing and adding liquid Chlorine up to SLAM
levels a minimum of 3 times a day. What kind of "shock" are you putting in the pool?

 

[IceShadow]

Sounds like filter efficiency is the thing to watch now.

- Have you tried checking the sand in the filter? As mentioned by V__25, any previous use of floc or often use of clarifiers can cause clumping and channeling - might need to do a deep clean (see link below) and verify the sand isn't clumped up and is nice and loose in the filter.

Deep Cleaning a Sand Filter

This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...

www.troublefreepool.com

- What is your clean PSI after backwashing, and at what PSI are you backwashing again?

 

[bc1080]

Thanks for responses!
The filter pressure is around 18PSI clean, I usually backwash if it goes above 24-25PSI or so. And like mentioned the backwash water is a milky white color.

The product I was using was cal-hypo 78% (sorry the label just called it "shock" and I went with that). I tried to switch to liquid for a few days, but the stores around here have started to shut down their summer inventories and finding pool chemicals is getting harder, so I've been forced to use the cal-hypo again for now (will try to find some more liquid today). I am doing the chlorine testing and putting in prescribed amounts based on maintaining recommended shock levels, not just adding set amounts. The only thing I haven't been able to do is check as much as necessarily recommended. We have not moved into this house yet due to a sudden medical issue, so I can only get over there twice a day or so during the week. I have tried to keep the levels at the proper range, but I know this might make things take longer too.

I looked at the label of a product I had naively used before the SLAM based on a friends recommendation, and it does say that it "works at a clarifier and floccant" but says it is "safe for sand filters." I followed the directions on that and hopefully it's not causing a problem but starting to think it might be part of the issue. I set the pump to recirculate when adding that and vacuumed to waste afterward like it said, but might have missed some I couldn't see.
We had a tech out to look at the equipment early because the pump wouldn't prime (found a suction leak), and the tech mentioned the filter we have "being a nightmare to access the sand" or something. The filter is a Hayward S200, I was planning on trying to replace the sand and check everything really well after this season, but was hoping to clean up the pool first so I didn't trash the new sand right away. I've been researching guides and walk-throughs on working on these filters.

 

[IceShadow]

Send a photo of your equipment, especially the filter, and we can see how we can assist about accessing the sand. Keep in mind that old sand filters better than new sand, so long as the sand isn't clumping up or stuck together.

For liquid chlorine, where are you checking? Usually you can find it at Walmart, Home Depot, etc.

 

[bc1080]

Thanks!
I found these pictures on my phone from earlier if it helps. I think the tech was referring to was having to remove all the bolts around the flange to separate the top for access, and then hopefully not breaking or cracking anything. I would think you could try to do a deep clean from the dome, but the tech wasn't sure about that.

I was able to find some of the chlorinating liquid at the home stores before, then found it cheaper at wal-mart. But at our local wal-marts on Wednesday their pool section was cut down 1/4 the size of what it was last week and they didn't have any liquid bottles or space for them anymore. I stopped by Lowes too and they were sold out, many stores I have been at recently have been out or low on stock. I was going to stop by a few more places today and try to find some (I'd think the home centers would keep at least some in stock all year).

 

[bc1080]

Updates:
I had missed a day because I was ill this week, and even after no attention for ~36 hours the FC was still 8.0, 0.5CC. I was finally able to find some liquid chlorine at HD (just rolled out a new pallet), so I've been using poolmath to figure the amounts to keep 12FC. The water clarity does seem to have improved slightly more since I posted. I can now see about 4 feet. By “see” I mean I can vaguely make out blurry colors at the bottom of the shallow end, especially using a bright light at night.

When I recently backwashed the filter, only two days later the pressure had already gone up 4-5 PSI. That seems faster than before, so maybe it’s starting to make some progress? And when I've tried to brush the bottom I seemed to create a cloud (maybe junk left from the floccant?), it kind of stirred up a murky cloud in the water and started circulating around. It seems like there is a sandy material sparsely distributed on the bottom, which I was trying to collect to one side so I can vac it easier.

I noticed that our deck concrete always seems to be dirty/dusty and our cars are covered in dirt after a light rain. Construction a few blocks down seems to be putting fairly heavy amounts of dirt into the air, I’m not sure if that can affect water conditions. I think I’ve determined what the other suction line is feeding the pump, seems to be a side port on the wall in the deep end (about 3 feet underwater). The old gate valve is likely shot, but it does have some minimal effect on the amount of strainer suction when open vs. closed.

 

[VinnyinNJ]

I'll let people who are more familiar with dealing with this help you but I just want to say you can use regular bleach found at food stores, Walmart and anywhere that sells it if need be. Make sure it's the real bleach not splashless or scented or anything else like that. Only difference is concentration is lower.

 

[duraleigh]

Can you post a set of your current test results? The SLAM process works every time it is followed precisely.

Sorry to sound harsh but it sounds like you are being a little haphazard and that's when the SLAM won't work. The process must be followed precisely.

 

[IceShadow]

What is your clean pressure? 4-5 psi increase probably puts you at 25% over clean value unless your psi runs really high clean. You should backwash at a 25% increase. That’s important to clearing up the cloudiness.

 

[bc1080]

Hi, my filter's clean pressure is around 18-19psi (which I was going to investigate a bit at some point). I did backwash after seeing that reading, and it was another large amount of that milky white backwash.

I understand that we might have caused things to drag out a bit, some of it was unavoidable or early mistakes on my end and now I'm just trying to do what I can to clean up the pool by staying with the SLAM process. Previously I didn't know all that I've learned since I found this site and had taken questionable advice from several people, even a pool store one time (they recommended the initial cal-hypo shock and algaecide). All the other stuff I mentioned was done before the SLAM, since I started I've been going solely by the website procedure. Our medical stuff is putting a strain on things and I am having to make a 30 mile round trip every time to check on the pool, so twice a day is probably the best I can manage for the immediate future except on weekends. However, the liquid bleach has been more straightforward and quicker acting, so I am glad I have some now.

The pool is still pretty cloudy after I swept it yesterday (we also got a little rain if that matters). My last test from today was 14.0 FC, 0.5CC. I hadn't tested CYA in a couple days (was 30 last time), I will recheck that and get back with the result. What other tests would help (I think some are inaccurate during a SLAM)?
I am starting to get worried that there may be other water issues at play. I have read some about phosphates and other contamination issues or situations when you need specialty additives like Revive, but I have not wanted to jump the gun on adding anything else yet. I've also seen mentioned that some situations may require higher FC levels for clearing, but don't know when that applies. Based on the amount of decomposing organic junk that came off the bottom, I am getting worried there may have been a major goof up when the pool was closed (like the previous owners might have covered the pool with a bunch of leaves and stuff still in there). Otherwise, as far as I can tell, they seemed to have essentially abandoned it last fall.

 

[W.J.Christy]

I am sorry to hear about your medical issues. I hope they are resolved soon. You're doing your best and that's all that can be expected.

Construction dust could be playing a part in your water clarity issues. Sand filters take more time to work than other filters do and yours may be having trouble keeping up with the dust and dead alge in the pool. Best thing is to keep back washing it. Maybe do so everytime you go there help it along. The deep clean may also be highly beneficial, especially since you don't know what was used prior to you taking over the pool from the previous owners.

Keep up the slam, increase the frequency you clean the filter, and maybe do a deep clean.

 

[Mdragger88]

The deep clean is definitely worthwhile especially since it sounds like what u used was a flocculant & there’s no telling what potions the previous owners used.
When u get to where u feel u have enough clarity to enter the pool safely u will want to do this to eradicate hidden offenders
*Check & scrub every nook & cranny where algae may hide (light niches, steps, drain covers, ladder handrails, skimmer throats/weirs, etc.)
About the phosphates- reducing them now is a moot point if u have them anyway.
It will not help in the current situation & often makes the water cloudy (which is the opposite of your current goal)
Keep with slam, eradicate the algae & it won’t matter how much “algae food” u have.

Phosphate Removers - Further Reading

www.troublefreepool.com

 

[IceShadow]

You can stick with the FC / CC during the SLAM. Honestly CC can even wait until your pool is clear, since it won't really matter if you have CC or not until you're looking to end the SLAM and just want to verify that it is 0.5 or less.

At this point you're down to filtering. If you want to try and speed it up / make sure it's progressing as it should, you could deep clean the sand in the filter. Here's the info on that:

Deep Cleaning a Sand Filter

This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...

www.troublefreepool.com

As mentioned, don't worry about anything but chlorine and filtering. You could speed it up by adding DE to the sand filter, but that does require some babysitting as if it works, it WORKS and will catch a lot of crud, so do it on a day you can spend some time there to check on it. Here's info on that:

Add DE to a Sand Filter

A clean pool filter will increase the efficiency of your pool! ... your filter are to backwash it, clean the manifolds and grids, and add new DE.

www.troublefreepool.com

 

[bc1080]

Thanks for well wishes! It's difficult since I have been dealing with a flareup of some chronic issues while my wife is recovering from an emergency surgery. She hasn't been cleared to drive yet, so I don't like leaving her alone too much.
I am planning to backwash more frequently, it seems to unload a bunch of gunk every time so it might actually be making progress. I did see that sand filters are noted for being the slowest by far.
As far as adding the DE. I have been looking into that option, if I did that how long do you think I should try to babysit everything? Like if I go on a weekend for 10-12 hours, is that enough time to ensure it is stabilized? It would probably be good to deep clean first, and I am going to try to make time to do that soon, assuming I can do it from the dome and not having to break the filter in half (I don't see why not).

Thanks for the info on phosphates too, somehow I had missed that page here before it was a good read.
In other news (figures for our luck), the pool also seems to have sprung some sort of leak. I don't see any major puddles back near the equipment pad or piping. But it's losing more water per day now than it has all summer. I am having to leave the hose on in the pool (about 15% flow) to avoid dropping too near the minimum level at the strainer every night. I used to only have to add water every 4-6 days. I will probably need to get a tech back out to look at it again, since I can't locate any major leaks.

I'm also not sure what it going on, but the CYA today now checked closer to 40. I will check that again and if that is accurate I'll need to adjust my poolmath parameters and target FC levels. I am also not sure what happened since I was following poolmath for chlorine but the FC got up to 17.0 (which might be closer to correct if that CYA is right). The water remains pretty cloudy, I may skip any agitation for a couple days to see if it clears up again so I can try to vac some more.

 

[HermanTX]

But it's losing more water per day now than it has all summer. I am having to leave the hose on in the pool (about 15% flow) to avoid dropping too near the minimum level at the strainer every night. I used to only have to add water every 4-6 days. I will probably need to get a tech back out to look at it again, since I can't locate any major leaks

Each time you backwash you are dumping water to your waste line. So that could be one cause of more then expected water loss. Also, if you vacuum to waste then that also lowers your water level.

The other point with regard to Pool Math app - it is dependent on the pool volume you use. I think in your original post you found some reference to the 28k gals however if that is off then that could be the error in the PM calculations. Just go with you have now.

You are doing great managing the health issues, a new home and a dirty pool. Obviously you show a lot of patience so just keep at it. Swing by HD to buy more liquid chlorine as that will be a need as this progresses.

 

[bc1080]

Right, I have noted the rough amount of water drop that it takes me to backwash. I usually prep for that by adding water before and after to try to maintain about the same level. I'm talking more like I put it up to a certain level one night and when I come back it's dropped more than expected. It seems to be losing about 1/2" - 1" a day, which is more than previously (which was 1/4" - 1/2"). The only thing I have done is I messed with the gate valve on the deep suction port a little but tried to put it back where it was (which was about 30% open). The owners had some paperwork where they wrote in 28k gals, based on pool size equation I got a higher number like 32-33k, but I am not sure how the sloping sides and stuff affect the volume so 28k could be about right. It's a 20'x40' with 8' deep end if anyone has something similar for comparison.

I had a water surplus after the storms the other day, so I did an extra backwash and a good amount of vacuuming. I have always been vacuuming to waste for now until I can confirm the pool is relatively clean. The last owners left a bottom cleaning machine (suction driven), and I have been tempted to try to let it run. But I am worried about what might be down there or being able to monitor it while it is running if I can't see it. The bottom of the pool has been difficult to work with for cleaning and vacuuming, it has a shallow ledge that goes around the edge of the pool and then sloping sides below the ledge and a sloping bottom to the deep end. I did do a long vacuum last night since the water was starting to clear a little and I pulled like a handful of sticks and acorns and stuff from the strainer afterward.

Speaking of the chlorine, I went by HD last night and they were completely out again. Luckily Lowes had some, but since they don't sell it in "packs" like HD it was a little more expensive per bottle, but I stocked up on 12 gals for now (I used up all 8 gals I bought at HD last week). As long as things are improving in the pool I think that is good sign. We can't really swim right now anyway, but would like to get it in shape for it to be used before the summer is over, haha, and eventually be able to be closed down properly.