SLAM Day 6. No improvement

[Joeysin16]

We were away on vacation and there was lots of rain back home. Chemistry must've been thrown off and pool was green. Can only see about 6" to 1' down clearly. Started SLAM right away (last Friday). Ph was 7.2 when starting. CYA was 40 (5,000gal above ground). Since Saturday (1 day in) free chlorine has been kept between 16 and 22. Combined chlorine has always been 0. Filter has been on 24hrs since starting (sand filter). There is no improvement. Did a SLAM when opening the pool this season and it took about a week and a half to clear, but at least there was some progress day to day. Not sure what else to try. Thank you for your help.



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Test Results 08-05-2021 @ 08:15 AM
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Free Chlorine: 21.0
pH: 7.2
Total Alkalinity: 80
Calcium Hardness: 350
CYA: 40
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[cowboycasey]

Welcome to TFP

Not sure what type pool you have.. At CYA of 40 you should be SLAMing at 16 FC not 21... it could bleach out a liner... with that said how long between checking FC.. I always recommend 2 hours and check again and bring back to FC 16..
FC/CYA Levels

With a sand filter it will take the longest to complete a SLAM..

What test kit do you have?

 

[Joeysin16]

It's a 5k gal above ground vinyl liner pool. I shoot for a FC of 16. I overshot last night, no big swings in chlorine though is what I meant. I'm keeping it at or above SLAM level at all times. Added some chlorine before going into work last night. Came home this morning and FC was 21. Just slept for 6hrs, and FC is still 21. CC is 0, which I thought was odd because shouldn't it at the least be killing the visible green algae? While I'm awake I test the water every 1-2hrs, it's holding the FC well though. When I SLAMed last time I'd add tons of chlorine and an hour later it would still be 0 (CC was high though). Now I may add a little bit in the afternoon and it stays 16 or above until the next day. I haven't had to add any chlorine today at all. I'm using the TF-100 pool kit. I also know sand filter could take the longest to clear up. Would've thought though that this high level of FC would kill the green and then I'd be waiting for the filter to clear up the clear, but now heavily Cloudy water. That's what it did back in June when I opened. Green was gone by day 2 or 3, but then took like a week for the cloudiness to disappear. This green hasn't relinquished a bit.

 

[mknauss]

Any copper containing products added to this pool water?

 

[Joeysin16]

Shouldn't be. No algeacide used and I don't have a heater.

 

[mknauss]

Shouldn't be. No algeacide used and I don't have a heater.

OK -- color just has that emerald green look. And elevated FC during a SLAM can bring it out.

Your pool volume is small. Since the SLAM is not working quickly, consider a drain and refill.

 

[cowboycasey]

I thought copper also, it is just that color green...

 

[Joeysin16]

Interesting. Don't know how copper would have gotten in there. Is it worth taking a shot to reduce it though before draining?

 

[cowboycasey]

I would take a sample to a pool store and have them check for it... We are not saying you 100% have it but it sure looks like it..

 

[Mdragger88]

You’ve never used perma salt or another “mineral” system like the frog have u?

 

[Joeysin16]

Nope. Never heard of those things

 

[Joeysin16]

I'll take a sample to get tested tomorrow for copper. May make sense because hardly any of my chlorine is being burned and my combined chlorine has been 0. Would expect something there if it was killing algae, right?

 

[mknauss]

CC is not defining of no algae.

But that green is way too vibrant for algae if you are maintaining a FC level.

 

[Joeysin16]

Thank you guys for all of the info! I'll take a sample to the store tomorrow after I wake up and let you know the results.

 

[Joeysin16]

Just brought the water to the pool store. They said no minerals are in the water and it must be algae.

 

[mknauss]

Back to an earlier comment. Unless your water is extremely expensive, drain it. Start over.

 

[Joeysin16]

Water isn't exactly the cheapest in NYC, so before draining today, decided to throw some algaecide in last night. Green is now all gone and I have that clear, but Cloudy water. Don't know why the SLAM wasn't killing it, but it apparently was algae.

 

[mknauss]

What algaecide did you use? Most algaecide does not kill algae, at most it prevents it. Sort of.

 

[Joeysin16]

Artic Blue by BioGuard. The guy at the store said they have 2 main algaecides. One is predominantly only for protection. This one he said aids in killing the algae as well. Figured whatevs, would cost less if it works than having to drain and refill. Added it yesterday afternoon and woke up to no green.

 

[Poolbreh]

Are you sure your reagents aren’t compromised?