Is my Intex SWG failing?

[AZLynn]

Just when I think I have everything under control, the Intex SWG isn't keeping up. I bought it last year so it's not brand new, but not old either.

I'm running the pump/filter 24/7 and the SWG 12 hours from 7-7. Pool is in full Arizona sun all day. No cover.

I just ran some tests and here are my results:

FC: .8
CC: .2
PH: 7.8
TA: 100 (crept up on me)
CYA: 70 (it was low, I added more, then it was high - FC was low then too but I blamed high CYA - so I drained some water and now it is perfectish)
SALT: 3000 (swg said it was high and there were deposits on the plates so I cleaned them with vinegar.)
Borates: around 40 I think. Using LaMotte (I think that's right) strips.

Oh, results are using Taylor 2600 and Taylor salt drop test. I also have the speedstir.

There is some scummy stuff on the inside of the skimmer just above the water line. I saw the same thing on a spot on the pool wall and the floating duck (no pucks, I just think it's cute) the other day too. I suspected a build up of the algaecide I used a couple of weeks ago mixed with sand (it is Arizona), but now I'm wondering if it was algae all along.

This is the first time I've tested positive for any CC in over a week too.

I'm planning to do the OFCLT or whatever it's called tonight, but is there anything else I'm missing? Shouldn't the SWG be able to keep up?

I'm going on vacation soon and didn't want my house/dog sitter to have to do anything but enjoy the pool. Now I'm thinking she might have to add bleach each day anyway. Should I just get some pucks for the duck for vacation? She knows nothing about a pool and I would rather not come back to a swamp and have to start all over again.

Did I mention it's Arizona so a couple of inches of water has to be added every other day anyway?

 

[AZLynn]

Just tried to wipe the scummy stuff off and it's stuck good and smears like grease. Is it algae? Any idea what kind?

Oh and the algaecide I had added was Bioguard Backup. It was probably more like a month ago instead of two weeks. I added it for two reasons. One, I had a swamp and figured the chlorine could use the help and two because I had backswimmers at the end of the season last year and read on here that it would help. I didn't see any once I started clearing up the swamp, but by then I was paranoid and figured the more ways I was attacking the algae the better.

 

[AZLynn]

Well I passed the OCLT I think.

After the testing last night I added enough bleach to bring it up to 4. An hour or so later it was 4. Just now it was 3.4 and maybe .2 CC (there was a tiny change) That's less than 1 loss so technically a pass but with no sun I think that might still be too much loss.

What do you all think?

 

[sarahspins]

I don't think your SWG is working as well as it could be - for your size pool you shouldn't need to run it for 12 hours, 3 or 4 is all that should be needed. When you cleaned it, did you soak it in vinegar until ALL the scale was gone? That can take much longer than the 20 minutes the manual suggests. I clean mine when I can start to see scale build up, I don't wait until it fails to work, and I normally have to soak mine for an hour or two (I run my SWG at night, so I normally set it up to soak in the morning, and check it when I remember, so it's more than ready to go by the time it's set to run again).

Keeping your pH a little bit lower than 7.8 may also help prevent scale build up on your SWG plates.

Was your SWG turned off for the OCLT? If so, and you passed, then I would strongly suggest that your SWG is just not generating enough chlorine. I add bleach by hand any time I test my water and my FC is lower than I'd like. Any SWG is really only good at maintaining a chlorine level, they just can't generate enough to bring it up for 0 quickly (or at least, faster than any organics in the water won't use it up).

 

[AZLynn]

I did the vinegar soak for a little over an hour. My manual actually says an hour and it was at least that. There was white stuff on the plates when I started, but I removed all of it. It looked like salt or calcium build up. I have hard water coming out of the tap so not much I can do about that. By the way, I removed the copper bars earlier this year. The SWG was giving a "high salt" reading, which I assumed was because of the build up but since the CYA was high, I had to drain some anyway. It's now reading 3000, which is the recommended. I'm wondering if it should be higher though.

The PH was lower, but it crept up on me while adding borates. This was the 48 hour check on the borates. I only got to about 40ish so I need more. I ran out of MA so I only added the borax for the MA I had on hand. I had bought what the pool calculator recommended, but my PH went higher than expected and I needed more MA to bring it down. I added some dry acid after the test last night to bring the PH and TA back down. That was the last I had of that too.

Yes, my SWG was turned off for the OCLT. While technically I passed, I still have that black slimy stuff at the water line in the skimmer and I think it was like a C or D grade and I would like an A. I suspect black algae has gotten a foot hold probably because the FC dipped too low when the CYA was too high and I didn't catch it in time. I've been trying to test twice a day at least right now, but work gets in the way sometimes.

This morning after the OCLT, I raised FC up a little above shock level for my CYA. The SWG is on. I know it's not recommended during shock, but I can't be there to add more chlorine because I had to go to work. The best I can do is add more this afternoon. I have to buy more first though. I only had 2 bottles of bleach on hand. I'm also going to pick up some pucks to supplement the SWG while on vacation. I read somewhere on here that rubbing the algae with a puck helps get rid of it too so I will probably try that also.

I think I'm on the right track, but if I'm missing something, please let me know.