My sad 2021 SLAM thread - sunscreen, not algae? Draining and refilling was the solution

4”? Gross. Do you have a picture?

6 people is a lot in our 450 gallon hot tub, and nobody is wearing sunscreen. 18 people in a 2200 gallon pool all wearing sunscreen to the point you had a massive ball of it in your skimmer? I suspect this was just a massive load on the chlorine, and oils don’t break down nearly as easily as typical bodily wastes (sweat/etc).


The guide for temporary pools (~3000 gallons or less) does indeed say this. I’ve recommended it as an option to people with Intex style pools even bigger if water is cheap. One time I let my 450 gallon spa get out of wack because I forgot to add chlorine after a night of partying, then forgot the next morning and the next two mornings. Water became cloudy. I tried slamming and after a week or more I still had some nasty CC’s and ended up draining and refilling anyway with the usual Ahh-Some purge. So I will never try to SLAM a hot tub if I let the water get that far out of wack again (which hopefully I will not do!).
Definitely my takeaway as well. I was a little surprised someone didn’t chime in on this thread recommending drain/refill though.
 
Came home and checked FC 10 ppm again! I haven’t lost any FC in a full day. I’ve not had this pool behave so well. We built it last year. Maybe all that drain scrubbing worked.

Interestingly, I found more black sunscreen in skimmer. It’s clearly not dropping my FC very quickly (yet).

Is this sunscreen just coating my PVC? Any tips from experts? I feel like I’m talking to myself a little bit here… best not to have the inmates running the prison… 🤪
 
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Thanks for the help. Is there a specific concentration of TSP recommended?

For your consideration: TSP is pretty nasty stuff. Make sure you're using correct PPE and try your best not to get any overspray on landscaping / vegetation. Also make sure you've rinsed them completely and the runoff doesn't end up in streams / lakes, or putting residual phosphates back into your pool. Algae eat phosphates.

Cleaning filters is something I actively hate, almost to the point of convincing the wife that we just need to chuck the cartridges and spend $200 every few months for new ones. But the cheapskate in me actively hates that idea. So I'm looking at other options. We're on well water and septic, with a stream in our back yard that feeds a community pond, so I'm not going to use TSP at my house. I've used blue Dawn dish soap in the same concentration (1 cup per 5 gallons) and soaked them overnight in a large garbage tub. Then I've tried several methods for rinsing them clean, and all of them aren't something I'm going to be able to do long-term without some runoff / erosion mitigation. Your cartridge system is likely way easier and more manageable, given the size of your pool.

The dish soap was very foamy and took a long time and a lot of messy water overspray to rinse off, so I'm considering trying using phosphate free dishwasher detergent (cascade, etc) or possibly even research if tide pods would work. We're already running those thru our system regularly anyway. I'd imagine someone on municipal water / sewer could easily and safely do the same. Most folks recommend either the single brass nozzle type sprayer or the aqua comb for the garden hose during the rinse cycle. I've had differing results with both. Seems like things go a little faster with the aqua comb. I used my small electric pressure washer on the first set, and I'm pretty sure that was a bad idea.
 
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For your consideration: TSP is pretty nasty stuff. Make sure you're using correct PPE and try your best not to get any overspray on landscaping / vegetation. Also make sure you've rinsed them completely and the runoff doesn't end up in streams / lakes, or putting residual phosphates back into your pool. Algae eat phosphates.

Cleaning filters is something I actively hate, almost to the point of convincing the wife that we just need to chuck the cartridges and spend $200 every few months for new ones. But the cheapskate in me actively hates that idea. So I'm looking at other options. We're on well water and septic, with a stream in our back yard that feeds a community pond, so I'm not going to use TSP at my house. I've used blue Dawn dish soap in the same concentration (1 cup per 5 gallons) and soaked them overnight in a large garbage tub. Then I've tried several methods for rinsing them clean, and all of them aren't something I'm going to be able to do long-term without some runoff / erosion mitigation. Your cartridge system is likely way easier and more manageable, given the size of your pool.

The dish soap was very foamy and took a long time and a lot of messy water overspray to rinse off, so I'm considering trying using phosphate free dishwasher detergent (cascade, etc) or possibly even research if tide pods would work. We're already running those thru our system regularly anyway. I'd imagine someone on municipal water / sewer could easily and safely do the same. Most folks recommend either the single brass nozzle type sprayer or the aqua comb for the garden hose during the rinse cycle. I've had differing results with both. Seems like things go a little faster with the aqua comb. I used my small electric pressure washer on the first set, and I'm pretty sure that was a bad idea.
I have worked with it before. So no worries there. I ended up doing a major rinse afterward. It really did the trick though. The article in pool school was quite helpful.
 
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9:00 PM - FC 9.5, CC 0.5
5:00 AM - FC 9.5, CC 0.5, crystal clear water.

I’ve only lost 2 PPM of FC in the last three days.

My pool has never behaved so well. I’ve always had at least 3 PPM/day FC loss even with the cover on. I’m only losing 0.67 ppm FC/day right now. Some combination of filter cleaning, drain cover scrubbing, and draining/refilling did the trick (for now). I keep waiting for the other shoe to drop.

Thanking the pool gods!
 
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Okay. I’m really at a loss here. I’ve been at near SLAM levels for almost two weeks now.
I have two sets of cartridges. I swapped out the sets 5 days ago and washed the old one with a garden hose. I just looked at and felt the old one - and it still has some gummy residue on the filter after washing.
I don’t know what to do. How do I clean these filters properly?
Any chemical treatments? I don’t have containers big enough to soak them in anything. Buy new filters?
Help.
I tried the ahh-some filter cleaner on my old filter as a last ditch effort to not throw $100 away and have the ability to have a ready spare. Previous symptoms were low flow rate and horrible vibration noise from the filter canaster. It worked! We switched filters recently and the old filter is working great. YMMV, but it might be worth a try.
 
I tried the ahh-some filter cleaner on my old filter as a last ditch effort to not throw $100 away and have the ability to have a ready spare. Previous symptoms were low flow rate and horrible vibration noise from the filter canaster. It worked! We switched filters recently and the old filter is working great. YMMV, but it might be worth a try.
Thanks for the tip. The TSP seemed to do a good job.
 
Just wanted to provide an update. When I don’t use the pool with the pool covered (I have an auto cover) I’m losing about 1.5 - 2 PPM/day. Plenty more depending on how many people use the pool. For example, I had about 7 people in the pool last Saturday, another 4 on Sunday, and by Tuesday it was back to its normal consumption. Seems like it needs a full 24h to “re-calibrate” to normal chlorine consumption. I’m sure its just leftover organics.
 
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