Success with SLAM!! What next?

[Carolyn]

So happy - finally met all 3 criteria for SLAM! The water was clear all along, but it sparkles now. Thank you all so much for your help & patience.

My test results this morning were:

FC 16
CH 275
TA 120
pH 7.9 (I read that this could be inaccurate due to high FC?)
CYA 60 (this is the test I'm least comfortable with, but definitely between 60 & 70)

Two questions:
1. Do I need to do anything about the TA? One place on TFP regarding SWG I read: "Adjust your Total Alkalinity to 60-80 ppm. (This is IMPORTANT!)"
But other comments made me think it wasn't necessary to adjust.

2. CYA for SWG is recommended to be 60-70. I tested the FC last night & it was 17. Ran the pump all night with the Aqua Pure set to 75%. FC had dropped to 16 this morning. We haven't cleaned the salt water cell since we bought the house last year - plan to do that soon. Should I add stabilizer, or wait till we clean the salt cell?

Thanks for all your amazing help!!

 

[Richard320]

Hold on a second.... If the SWG was on all night you didn't pass the overnight loss test. You're not done with the SLAM. When you lose 1 FC or less overnight without adding any chlorine via jugs or SWG, then you've passed. Sorry. For that matter, if CYA is close to 70, you'll need to maintain FC up at 28 FC, not 16 or 17. That's not high enough to kill algae faster than it can reproduce. You need to do it right or you'll be posting again in a couple weeks that your pool is cloudy and/or it looks like your SWG isn't working because you have no FC.

That being said, once you DO actually pass the OCLT, the SWG will be off and you'll leave it off until FC drops below 10 in a day or two and then you can retest everything and deal with pH and TA and CYA if necessary.

 

[Pool Tool]

Are you sure you actually passed the OCLT? If you had a 1 ppm drop in FC while running the Auqa Pure at 75% all night something is still consuming FC. And quite a bit of it. I would shut off the SWCG, bleach back up to SLAM levels and repeat OCLT tonight. If your FC drops fast today consider letting it fall to <10 and retest ph and then raise back to SLAM. Listen to the experts, but I think you are fine to omit adjusting the ph until you run another OCLT.

TA is important but secondary to irregular FC consumption. Fix FC first then attack TA. High TA will cause rapid increase in PH, which is why it should be lowered with SWCG.

 

[Carolyn]

Sorry to confuse everyone. I did the OCLT test night before last, not last night. Last night was just to test the SWG, as someone here suggested to me earlier. I slammed at 28-31 levels for the 6 days prior with the SWG set to zero. When I did the OCLT, the night reading was 31 and the morning reading was 30.

 

[DaninFLA]

congrats!

left your FC drift back down to your recommend FC levels. once its under 10 go ahead and figure out pH. also, redo your TA results then too to make sure. adding MA to lower the pH will reduce TA. if your pH is holding steady and not rising, wouldn't worry about.

as far as CYA goes, you can bump that up but I don't think its critical. I have a SW pool too and have been at 60 CYA for a while now and the system has been keeping up fine on FC. Im just now in the process of bumping it up.

I would keep your CYA at current levels for the next couple of weeks and would re-do the OCLT in a week just to make sure you are good to go. I wouldn't feel comfortable with a 1ppm loss overnight, I waited till I had 0.5 or less loss. once you add the CYA, its in.

 

[Richard320]

Sorry to confuse everyone. I did the OCLT test night before last, not last night. Last night was just to test the SWG, as someone here suggested to me earlier. I slammed at 28-31 levels for the 6 days prior with the SWG set to zero. When I did the OCLT, the night reading was 31 and the morning reading was 30.

Something still isn't right. If you started at 17 and the SWG was on all night at 75%, your FC should have gone up not down. I'd figure you'd see at least 20 FC in the morning. There was no sunlight to destroy it. So either something is eating it or the SWG isn't working.

 

[Carolyn]

Yes, Richard - that's what started me looking for help when I found this site. I feel like the SWG isn't working correctly. When I asked about the SWG, everyone advised me to SLAM first to make sure there wasn't anything eating the chlorine. Now I'm back to working on the SWG.

 

[Donldson]

With your SWG off do an FC test and record that. Then fire up your SWG at 100%. Give it a couple minutes to get going and do another FC test with water straight out of the return. Post those numbers up here, that will give us an idea what your SWG is doing.

From my HTC One via Tapatalk

 

[Carolyn]

Ok, I did the two tests that Donldson suggested and the FC levels were exactly the same. Does that mean the SWG isn't working?

 

[DaninFLA]

Ok, I did the two tests that Donldson suggested and the FC levels were exactly the same. Does that mean the SWG isn't working?

I would remove the cell first and clean it. that needs to done periodically. remove the cell, and soak it in diluted muriatic acid, I believe I did a 1:5 dilution. let it sit in there for a while and then rinse. that will remove any calcium deposits on the cell. replace it and redo the test.

also, how did you collect the water coming from the SWCG? I did the test and I used a bucket on the side of the pool, and then I got one of those floaty noodles and placed it over the jet and directed the water into a bucket, lol.

 

[Donldson]

The water coming our of your SWG should have measurably higher FC, so something is up. Next step is to clean the cell as DaninFLA said. Hopefully that is all it will need.

I want to point out too, you may now be thinking that the SLAM was a waste of time. Remember though, with your SWG on the fritz the FC was dropping and something was growing or going to grow. Since you did the SLAM your water is clean and now you know how to keep the FC up using bleach until you get the SWG working. Doing the SLAM saved you a lot of headache going forward and your pool will be in great shape when you get your SWG back online. So great job getting that done and avoiding those problems!

 

[Carolyn]

thanks again, everyone. Dan I think you're right about the cell needing to be cleaned. After I did the 2 tests that Donaldson suggested I checked the display panel and the cell light was not on and then I got a no flow message. Both those were new. The operator's manual says those two conditions can be caused by a cell that needs to be cleaned. So that will be the next step.

Believe me, I don't think the SLAM was a waste of time. If nothing else, I learned a huge amount about the testing. And though the wate was clear, it didn't sparkle like it does now so there probably was some algae in there. And best of all, I lost 1.5 pounds running up & down the steps doing all that testing. Life is good!