To Slam or not to slam?

[outbacktommy]

I didn't test my water right at opening because I thought I'd give my SWG a chance to catch up from the winter's sleep. Pool opening never gives me any surprises, the water is always as clear as the summer before. But...

My CC is 2.0
FC = 5.5
pH =7.6
TA = 225
CH = 180
CYA = 40
Salt = 3100
Temp = 67

I'll be getting the CYA up to 70 in a week or two- I had to replace a bunch of water last year to get the CH down and didn't have enough spare CYA lying around to finish this last year.
The TA has always been high, and I just built a spray feature to use this year to aereate the water to fix this one.

Nearly all of the references to SLAMming relate to problem water, which I don't have, but the CC is 2.0. What is my best course of action? Can I knock it down with the SWG on super-chlorinate for 24 hrs, or will I have to add bleach? I've never had an algea problem, it seems like overkill to go through a full slam treatment.

 

[kabutotx]

CC could be from chlorine fighting algae or something not seen like ammonia. It also could be a bad reagent. Try to do an Pool School - Perform the Overnight FC Loss Test (OCLT). That will let you know. Or just do a short SLAM.

 

[outbacktommy]

OCLT came back with 0.1 clorine loss. Not sure what you mean by a short SLAM, but I'll start that process over the weekend. Is CC=2.0 considered high, or just elevated?

 

[kabutotx]

No need to SLAM with that loss. I do know some chemicals can be registered as CC. Have you added anything except the basics like algaecide, clarifiers, etc.

 

[outbacktommy]

Kabutotx,
I didn't get your post in time. SLAM started yesterday evening. As stated above, CYA is 40. FC is held at 19 and CC is still 2, after 24 hours. I'm kind of guessing at the right SLAM levels because of the auto cover. I have an outdoor, in-ground pool, but it is not exposed to the air or sunlight except when in use, which makes it a lot more like an indoor pool. Water being 63 degrees and May in Minnesota, the pool wont be open for use for another 2 weeks at least. I plan to open the filter and spray off the cartridges tomorrow. The water is crystal (always) and there is no leaf debris (rare).

To answer your question about chems, algaecide goes in at pool closing only. No clarifiers. Last year was the first year our pool ever saw CYA. I had it at 60-70, but it strayed from that target when I replaced 1/3 of the water to get my CH under control. I will be getting it back up to 60-70 after the CC is back to 0. My theory is that this level of CYA will buffer the wild FC swings that happen from the irregular weekend pool parties- please chime in if you think my theory is 'all wet'. I am very much not an expert, and my pool equipment combination is a bit out of the norm.

 

[mknauss]

Your signature shows "always covered". CC's are burned off by UV on the water surface from the sun. So you need to open the cover every few days for a few hours to let them outgas.

MPS (non chlorine shock) will also show up as CC's for quite some time.

Take care.

 

[outbacktommy]

That's something I missed. I knew that FC went away with sunlight, but I didn't see where CC also burned off w/ sunlight. I'll remove the cover today.
Tom