New pool,swg hard to dial in, not sure its working right since salt isn't needed

Jump to latest Follow Reply
F

flipr

0
LifeTime Supporter
Aug 20, 2015
130
Punta Gorda, FL (SW FL)
Okay, pool was new in July 2015. After 1 month, they added salt, and I have a Pentair IC40 swg.

We check salt levels weekly, using Taylor kit, and it bounces between 3800 and 4200 last week 4200 after 3 months. We've not added salt since conversion in August, going on 3 months now.

Past 3-4 weeks, Cl level has been dropping. I've bumped % from 20% to 60%, adjusted run time longer, all to no avail.
Manual says to check for cleaning every 3 months, pulled out of unions, plates are completely clear. Hooked back up, all green lights on indicators.
Poolmath says to run at Cl of 6, yesterday it was 3. Been adding bleach almost daily, 4-5 times a week.

We've had a crystal clear pool since day 1, we've never shocked or SLAM the pool, as chemical results didn't show a need.

Is our salt usage normal? Should we go 3 months without adding any, and have test results show differing readings?

Thanks much
 
Salt is not a consumable chemical in the pool water. I have not added salt to my pool in over three years. The chloride ion (Cl-) from the salt get converted into chlorine gas which dissolves into the pool water and forms hypochlorous acid (HOCl, where the chlorine is Cl+). When the chlorine oxidizes an organic or kills a pathogen, the chlorine (Cl+) gets converted back to chloride (Cl-) and the cycle continues. The only way salt is lost from the water is through water exchange - pool water is either removed from the pool through spalsh-out or backwashing or rain water dilutes your pool water in the form of overflow. Liquid chlorine, or bleach, has excess salt in it from the manufacturing process so it too adds salt to your water. As well, most municipal water supplies have chloride salts in them (just not high enough to taste or be harmful).

If you are running your IC40 and it is not keeping up, there could be multiple problems - nascent algae bloom (clear water is NOT a sign of clean water), not enough stabilizer in the water (CYA) or a malfunctioning SWG. Given your pool size you should definitely NOT be having to add bleach, the IC40 should be more than enough.

Please post a full set of test results (FC, CC, CYA, pH, TA, CH, salt) and we'll do our best to help you diagnose the problem.
 
You have added salt, every time you've added bleach. Down near the bottom of poolmath where it says effects of adding chemicals it can tell you how much you've added per gallon, provided you input the pool volume and the bleach strength.

Test results will tell us if your CYA level is too low, and if you have high CC.

An overnight chlorine loss test will also tell you if the problem is sunlight or organics.

You can check the SWG operation by capturing a sample straight out of a return while the SWG shows generating. FC should be much higher than the pool FC level overall.
 
Thanks much, going to do the OCLT test tonight. Didn't even think about bleach adding to the salt! Duh, there's a reason I didn't like chemistry in high school.
My wife has been doing the samples, and now she says she isn't sure she did them right, so, I will run full set in AM.
Getting cooler now, and not as much full sun, pool is on north side of house.

in the past couple days results were

fc 3 (increased to 6 with bleach, reading 5 today)
cc 0
ph 7.5
cya 75
ta 80
ch 380 (this has usually been around 325, just spiked this last test to 380)
salt 4200
 
Muriatic acid (34.15% HCl) also adds chloride to the pool. For your 9,600 gal pool, every gallon of MA added will add ~62ppm chloride as registered on the K-1766 test kit.
 
Cleaned filter last night, disconnected SWG, bumped up CL to 10 for OCLT
was at 8 this morning, so I failed the OCLT
Other results
ph 7.8
ta 70
cya 55 (never been this low, but I measured properly holding at waist height instead of leaving on counter)
CH 380 jumped up 60 ppm in last couple weeks

They are building a new house next door, not sure if sawdust and such has gotten in, maybe that's where some of the organics have come from. Hasn't rained much.

So it looks like a SLAM is needed. Do I adjust any other chemicals before SLAM? Pool Math says I need to go to 22 ppm for shock, is that the right number I'm looking for?

THanks much
 
Round your CYA measurement up to 60 which would make your SLAM level 24. Really important to also lower your pH to 7.2 before your start the SLAM as it won't read accurately when your FC is over 10, then its really just important to maintain an your FC level of 24 until you SLAM is complete.
 
flipr said:
Cleaned filter last night, disconnected SWG, bumped up CL to 10 for OCLT
was at 8 this morning, so I failed the OCLT
Other results
ph 7.8
ta 70
cya 55 (never been this low, but I measured properly holding at waist height instead of leaving on counter)
CH 380 jumped up 60 ppm in last couple weeks

They are building a new house next door, not sure if sawdust and such has gotten in, maybe that's where some of the organics have come from. Hasn't rained much.

So it looks like a SLAM is needed. Do I adjust any other chemicals before SLAM? Pool Math says I need to go to 22 ppm for shock, is that the right number I'm looking for?

THanks much
Click to expand...
Adjust pH down because once you raise FC above 10 you won't be able to test it. Then hit it hard with bleach and do not neglect the areas where algae can lurk -- behind lights, beneath steps, inside the skimmer throat.
 
Thanks, was away from computer over weekend, but started SLAM Saturday.
WEather was overcast most of the day, readings had dropped, so I kept adding bleach during day. Scrubbed sides well.
OCLT Saturday night, lost 2 ppm, so upped the bleach again for Sunday.
Was gone during day, came back and had lost 5 ppm, sun had been out.
Brought back up, measured for OCLT again Sunday night
Lost 5 ppm overnight, so still not where we need to be.
I did reduce ph at start, dropping to 7.2 per the math. went from 23 to 18
Do I need to reduce ph again, 3 days into this?
Water still looks clear to the eye, cc test always reads 0, but cl won't maintain overnight.

Thanks all for the help.
 
No just run with it now- remember your pH won't read accurately over 10FC. I think that you might need to try to retest and bring up to SLAM levels a bit more often if you can- it should make it go quicker. It's all about maintaining your FC at SLAM levels to kill the algae. If your SLAM level is 24 try and slightly overshoot by a couple of FC to ensure that its at or above this level more times than not.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Jezza said:
No just run with it now- remember your pH won't read accurately over 10FC. I think that you might need to try to retest and bring up to SLAM levels a bit more often if you can- it should make it go quicker. It's all about maintaining your FC at SLAM levels to kill the algae. If your SLAM level is 24 try and slightly overshoot by a couple of FC to ensure that its at or above this level more times than not.
Click to expand...

Thanks, bumped it up, was 25 down to 22, so bumping back up again. drop to 22 came after 2+ hours, sun is out, but not overly hot in Central FLorida today
 
ping said:
Since you are losing the FC and dropping below the recommended SLAM level between tests, raise the FC to 28. The idea is to be close to the SLAM level without dropping below it between tests.
Click to expand...

Thanks, will do, failed OCLT last night, haven't been able to get into pool to remove light and scrub there. Steps are gunnite, scrubbed skimmer box, ran kreepy krawly all night to vacuum floor and walls well, brushed again this am. Still a work in progress, thanks all for help
 
SLAM Day 4 update

Got in the pool last night, scrubbed light frame very well, but couldn't get the set screw to break free. Read elsewhere here, that setscrew should come out, and allow light to tip out of the niche.
Couldn't break the threads at all, so will try different tools tonight. Hard to get a good grip on screwdriver while underwater.

As for the OCLT, failed another, after bumping FC to 28, dropped to 26 this am. With all the testing, and using 50 drops of R0871 each test, we went thru a 2 oz bottle yesterday alone. Didn't want the FC to drop too much during the day so we tested every 1.5 hours, and after adding bleach.

Will update progress tomorrow, hopefully we can find reagent locally, as our mailorder from TFKits will be a couple days yet.

Thanks again all.
 
You may need to clean your filter out as well if you already have not done so.

Good luck.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006
 
UPDATE

We weren't able to test water all day as we ran out of R0871. Tested at end of day, was 20, bumped back to 28

FINALLY got the light out, screw was tight, and I couldn't get enough leverage on my feet to turn the screw driver. FINALLY found enough leverage and pulled light. Nothing seen i the niche, but I scrubbed out some plaster. too dark to see. However I did find some slime on the 4' of cable running from lamp to connector at back of niche.

I used a towel and straight bleach and scrubbed the cable and lamp housing all I could when outside the water line. I will let it sit overnight outside of pool. Hopefully, fingers crossed, we will pass OCLT tonight.
 
Thursday update

Still burning thru chlorine, dropped 7 ppm overnight. I wasn't able to scrub out the niche last night, but my wife took a brush to it this morning, and the clean brush turned green quickly.
Boosted chlorine back up to 28 this morning, will check again around lunch time. Light is still out of pool, so niche is open.

IMG_1540.jpg
 
If you have something like a Mr. Clean MagicEraser, that would work a lot better on the plastic niche surfaces. Brushes are ok, but the melamine foam of the MagicEraser will pull all the gunk off the surface. I use them to clean the plastic surfaces inside of my skimmer and it takes off all the stains.

Just a suggestion. Keep up the good work as it sounds like you found yourself with a good algae bloom.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply