I'm SLAMing and desperately need guidance

Ignoramus

Gold Supporter
Sep 28, 2022
113
North Houston, TX
Pool Size
24000
Surface
Plaster
Chlorine
Liquid Chlorine
Hello everyone!

Here is situation:
  1. The pool belongs to my kiddo's school. And I need to be very frugal with money and resources.
  2. The pool is 24K gallons, plaster, multiport valve and DE filter with hard-wired (or hard-plumbed?) waste line.
  3. It is 30 minutes drive from my house, so my hours with it are limited to 8a-3p, maybe till 5pm.
  4. I've began SLAMing Oct 31.
  5. Pump ran 24/7.
  6. I've added chlorine at least twice almost every day.
  7. I've brushed the pool with stainless steel brush every day.
  8. The filter develops high pressure (35 psi) about 30 minutes or so after wash and DE reload. I assume it gets full of crud that quickly - I started with vivid green pool.
  9. When filter gets full, the flow goes to almost nothing. I have flow gauge and there's nothing from returns.
  10. At this point I switch pump to recirculate, and wash the grids.
  11. 5 days into SLAMing, I found a crack in the manifold. I patched it with JB Weld Plastic Weld (2 parts clear epoxy) and let it cure over the weekend. I ran it again once (same 30 minutes until pressure goes to 35 psi) and the crack opened up again.
  12. At the same time, I found broken handle spring and bad spider gasket in multiport valve. It has been leaking DE back into the pool during backwash and it has been leaking water into waste line.
  13. New spider gasket, spring, spring o-rings installed.
  14. Return lines were checked by plugging all returns but one and recording the flow. The flow to farther return ports is a little less: 75 gpm vs 80 gpm on closer ports.
  15. There are 5 return ports with eyeball covers.
  16. I have lost my head after few days of no progress so I added borax at a wrong time.
  17. And I've tried clarifier in the pool after good results in test bucket. Without filter running, it didn't help.
  18. Logs: PoolMath Logs
  19. I have TFT-100 test kit.
What do I have now:
  1. The water is much lighter, but has green hue and is very murky.
  2. I am losing FC so there's live algae in there.
  3. I can see few spots in shallow parts but it feels that I still have a big infestation. But I can't see other hideouts because the water is opaque, so I just brush and focus really hard scrubbing on one section a day.
  4. The stairs have visible algae spots so they get brushed hard every day.
  5. The filter can't be run overnight.
  6. I can't keep washing and adding DE few times every day - it takes a lot of water and about $8 worth of DE every time.
  7. Water is about 70F.
  8. When I figure out how to share my logs, I'll add them to this post.
Questions:
  1. Did I miss some info about DE filter usage during SLAMing?
  2. I speculate that filter clogging up this quickly have caused the crack and I'm afraid to break new manifold the same way with my improper method.
  3. Without constant filtering and with huge amount of crud floating in the water, would it be more practical to use floc, vacuum to waste and then keep going with SLAMing and brushing where I can see algae spots? Loss of water feels like a moot point as I will be losing it by daily washing of filter grids. Besides, I'll save some on not running the pump for one night.
  4. I'm also considering putting on full wetsuit and going into the pool. I'll feel slimy spots with my feet and will be able to do intense brushing at those spots.
  5. I'm open to suggestions of experienced users. The above is just what I can come up with in my ignorance.
Thank you for all and any help!
Feeling the profound depths of my ignorance, yours truly,
Ig20221108_151112.jpg20220908_081146.jpg
 
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You need to run the pump 24/7 and bring the FC back to SLAM level more than twice a day to stay ahead of a bad algae problem that you have. You can do the first part of the SLAM with the filter in recirculate until you kill most of the algae but eventually you need to be there and go through the filter cleaning cycles to clear the dead algae.

Why can't you drain the pool and start with fresh water? Given the equipment and time limitations you have that will save you a lot of time, effort, and probably money.

What test kit do you have?

Why are you messing around with acid and TA while dealing with a SLAM?

The SLAM Process works when you follow it step by step without shortcuts. From looking at your PoolMath logs you are not doing that.

Drain and refill may be the best for your situation.
 
It looks like you made some progress but there are 2 critical parts of the SLAM which are keep FC at SLAM level and circulate 24/7. I see the CYA testing is 40 or 45ppm. TFP procedure is to round up so say 50ppm which means your SLAM FC should be 20ppm. I see you only reached 15ppm once. Even if you can only be there from 8-5pm you could test 3 times in that interval and ensure FC is at SLAM level. It will drift down overnight but then test first thing next morning to bring it back up to SLAM.

Since you are having filter issues, can you vacuum to waste? That way you are getting rid of dead algae however you will also drain water which needs to be replaced which brings up the obvious.....

I agree with Allen - what is keeping you from draining the pool and refilling? What you are spending on liquid chlorine now could offset cost of new water for pool. You may need to still SLAM after new water but it will be much easier as you should get rid of most of the algae.

I think it is great what your are doing given some of the limitations you have to work but draining may put you in a better place to solve this.
 
To answer questions:
  • About FC levels: After every test with low FC, I have added suggested amount of chlorine, but didn't recheck the levels. So most of the weekdays the water was at SLAM levels.
  • I have TFT kit.
  • Yes, I can vacuum to waste.
  • TA adjustment was following suggestion of PoolMath.
  • It also suggests increasing CH and I'm looking into options.
My questuons:
  1. When you say "drain and refill", is that complete drain? I did think about it given how much water is lost in all those filter washes and cost of chlorine...
  2. How much water would I lose vacuuming to waste?

Thank you for the help! It is appreciated!
Ig
 
During the SLAM Process you do not adjust pH, TA, or CH.

Yes, complete drain and refill with fresh clean water.

Test the fill water you will use and post what the pH, TA, and CH of it is.

 
Is this an indoor pool or outdoor pool?

Post pics of the pool and equipment.
 
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In my opinion, filtering the water while the water is still green is a waste of time especially with a DE filter. If you’re not replacing the water, just recirculate 24x7 and get way more chlorine in there, and even test after you’ve added chlorine to make sure you reached the level you needed. The estimate that poolmath gives is just an estimate.
 
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In my opinion, filtering the water while the water is still green is a waste of time especially with a DE filter. If you’re not replacing the water, just recirculate 24x7 and get way more chlorine in there, and even test after you’ve added chlorine to make sure you reached the level you needed. The estimate that poolmath gives is just an estimate.
Gotcha. From now on i will retest after adding chemicals.
Thanks!
 

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Test the fill water you will use and post what the pH, TA, and CH of it is.
Source: pH: CH: TA:
Tap water. 8.2, 50, 90
Pool. 7.2, 250, 110

The reason I messed with pool TA and pH, is that before SLAM I relied on Leslie's tests of these and they seemed to be ok. After heavy rain I did complete chemistry and PoolMath wasn't happy with CH and TA.

 
This is what pool vac (Polaris P825 with sand and sediment filter cartridge) has been picking up lately. It looks like DE to me. And the water draining from vac filter looked the same milky and murky as pool water. Could the cloudiness be caused by DE? It had been pushed into the pool by cracked filter manifold and bad spring in multiport valve. 20221109_094037.jpg
 
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I had been making diagram of the pool equipment. Would that be more helpful?

No, we can understand more from seeing good large pictures that let us see all the equipment and follow the plumbing.
 
Source: pH: CH: TA:
Tap water. 8.2, 50, 90
Pool. 7.2, 250, 110

That is good fill water.

After heavy rain I did complete chemistry and PoolMath wasn't happy with CH and TA.

Do not become a slave to the robot. PoolMath gives suggestions that may or may not make sense for your situation. CH and TA are not important when you are looking at a green pool.
 
This is what pool vac (Polaris P825 with sand and sediment filter cartridge) has been picking up lately. It looks like DE to me. And the water draining from vac filter looked the same milky and murky as pool water. Could the cloudiness be caused by DE? It had been pushed into the pool by cracked filter manifold and bad spring in multiport valve.
This is what DE looks like when wet so that is probably accurate. A cracked manifold will cause this to happen. You still have algae so don't think that the cracked manifold is your main issue. It is an issue that that needs to be addressed so best to plan to purchase a new manifold. Can you provide the make and model of the filter? You may want to put the multi-port valve on recirculate to avoid going through the filter however this will not capture any dead algae so you need to manually vacuum it out unless you have considered draining and refill.
 
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Get the filter repaired or replaced before you refill with fresh water. You don't want to be dumping DE from a busted filter into the new water.
 
Fix the filter or replace it.

Drain the pool and refill it with fresh water.

After the refill add 30 ppm of CYA and then SLAM Process to get rid of any residual algae.

How do you chlorinate the pool?

What are the target water chemistry you are required to maintain in the pool?
 
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