Am I on the right track? New home w/pool

[dawndenise]

I've moved to FL and now have my second pool (first one I maintained for 4 years, inground). Prev. owners said they'd had a recent problem with low chlorine and replaced the flow sensor on the SWG. When we moved in, the SWG was on 30% and pump was running for 8 hours.

My first tests with my oft-refilled PS-234S yielded:

pH 7.2, maybe less
FC 23.0
CC 0
TA 90 (test turned blue initially, then yellow at 90)
CH 320
CYA 90-100
Salt 3000

I turned off the SWG!!! Slowly, but surely the chlorine has been dropping. Now, 9 days after my initial tests and no swimming, I tested:

pH 7.7
FC 10.0
CC .5 (maybe less)

I'm thinking I could do a partial drain to drop the CYA into the proper range for the SWG but is it really necessary right now? With the higher CYA, is 10 FC swimmable? I'd like to drop the FC just a bit more (maybe wait another day) and then turn on the SWG at a low level and monitor the FC level and add some muriatic acid.

Any other recommendations, thoughts?? My signature reflects this "new" pool.

[CarlD]

I'm no SWG expert but after reading hundreds of posts it is clear that SWGs require higher-than-normal CYA levels--80ppm being about the recommended level. If you have the SWG's manual, read it--it should tell you.

If your pool is uncovered, that would explain the rise in pH--you've somehow been aerating it and that raises pH.

A CC of .5 may actually be only .2--did you re-do the test using 25ml of water instead of 10ml? In that case, each drop of the re-agent only represents .2ppm, not .5ppm. Clearly, .2 is STILL only an indication of the maximum the CC can be.

You MAY want to briefly raise your SWG level to kill any CC you have--0 is the best number. Or you can shock the pool with bleach or liquid chlorine. Also, you should also find that with your SWG you can keep your FC at a lower level than the "Best Guess" table indicates--because the chlorine levels are far most constant, plus the salinity is a growth inhibiter for algae.

I hope this helps a little.

[waterbear]

I'm no SWG expert but after reading hundreds of posts it is clear that SWGs require higher-than-normal CYA levels--80ppm being about the recommended level. If you have the SWG's manual, read it--it should tell you.
Depending on the manufacturer it is usually anywhere between 50-100 ppm with 60-80 being the most common. In actual practice 80 ppm works out well unless there is a lot of sun in such places as Florida, Arizona, California, etc. Then bumping it to 100 has been found beneficial.
If your pool is uncovered, that would explain the rise in pH--you've somehow been aerating it and that raises pH.
SWGs areate the water by producing hydrogen gas at one of the electrodes when they are generating. This causes CO2 to outgas and the pH to rise. This is why running a very low TA helps with pH stability.
A CC of .5 may actually be only .2--did you re-do the test using 25ml of water instead of 10ml? In that case, each drop of the re-agent only represents .2ppm, not .5ppm. Clearly, .2 is STILL only an indication of the maximum the CC can be.

You MAY want to briefly raise your SWG level to kill any CC you have--0 is the best number. Or you can shock the pool with bleach or liquid chlorine.
Not needed, Just turn the unit on and the CC should be gone in abourt 48 hours.
Also, you should also find that with your SWG you can keep your FC at a lower level than the "Best Guess" table indicates--because the chlorine levels are far most constant, plus the salinity is a growth inhibiter for algae.
With a CYA of 100 keep the FC at about 5 ppm.
I hope this helps a little.

Hope this clears some things up.

[CarlD]

Evan knows this stuff for SWGs better than I do. I was close, of course, on most of the numbers but he KNOWS much more precisely what they should

However, I DID forget that SWG pools frequently experience rising pH so you end up adding a good bit of muriatic acid to get them back down. I thought it was just due to the out-gassing of an uncovered pool with a lot of natural aeration....my bad!

[dawndenise]

Thanks Carl & Evan. Just the info I needed! My previous pool and I had a nice "understanding" and we got along just fine with no problems...also an inground gunite, although with a different finish, and the same brand SWG.

But this pool is in a totally different environment, so I'm not as confident in my approach, especially when the CYA is approaching 100 whereas my last pool ran nicely at about 60 - with SWG. From my limited experience, I think there's a sweet spot with every pool where it likes to settle, as far as readings are concerned. I knew my last pool...now I just have to get acquainted with this one.

And, Evan, you mean this isn't the rainy season yet???!!!

[waterbear]

And, Evan, you mean this isn't the rainy season yet???!!!

Wait unti Octoboer! Good new is once Hurricane season is past just about all of Florida is considered high dessert!
Where in FL did you end up? The rains are worse in land than on the coast, IMHO.

[waterbear]

I've moved to FL and now have my second pool (first one I maintained for 4 years, inground). Prev. owners said they'd had a recent problem with low chlorine and replaced the flow sensor on the SWG. When we moved in, the SWG was on 30% and pump was running for 8 hours.

My first tests with my oft-refilled PS-234S yielded:

pH 7.2, maybe less IF it is 7.2 leave it. It WILL rise with a SWG!
FC 23.0 Has the pool been covered? If it has uncover it for several hours every day (ideally while the pump is running for the full pump run time) . I would leave the pump at 8 hours and turn the output down. Also, once you start using the pool and have a bit more of a chlorine demand this will change and you might need to turn the output up.
CC 0
TA 90 (test turned blue initially, then yellow at 90) High FC levels will beach out one of the indicatiors used in this test but the test is still valid with the blue to yellow color change, just harder to see. You CAN add a few extra drops of the chlorine neutralizer (first reagent) to help overcome this when you know you have very high chlorine. I would actually think about lowering this to around 70 once your pH comes up as you will have better pH stability and less acid demand with a lower TA
CH 320
CYA 90-100 Leave it alone. It's fine for a salt pool. Level is slightly high for an Aquarite but if you keep your FC at 4-5 ppm you will have no problems at all. It will drop on it's own during rainy season, which is coming up very soon here in FL!
Salt 3000 A bit low but livable. I like to keep it closer to 3400 ppm to compensate for the rains we get here in FL. That way wyen the water level goes up the salt is still ok.

I turned off the SWG!!! Slowly, but surely the chlorine has been dropping. Now, 9 days after my initial tests and no swimming, I tested:

pH 7.7
FC 10.0
CC .5 (maybe less)

I'm thinking I could do a partial drain to drop the CYA into the proper range for the SWG but is it really necessary right now?
NO!
With the higher CYA, is 10 FC swimmable?
In the state of Florida 10 ppm is considered swimmable in a commercial pool with CYA of 30-50 ppm (I've taken care of comemrcial pools here in FL. Over 10 ppm then a pool is closed. You are fine--go swimming!
I'd like to drop the FC just a bit more (maybe wait another day) and then turn on the SWG at a low level and monitor the FC level and add some muriatic acid. Don't add acid yet.
Wait for the pH to climb to 7.8 and then don't lower it below 7.5. This will maximize time between acid additions and prevent problems. The lower the pH the faster it will rise (don't ask me to explain, you will be sorry!) Never let the pH get above 7.8 or you are asking for problems.

Any other recommendations, thoughts??
Add borates to 50 ppm. It will help a lot with pH stability.
My signature reflects this "new" pool.

Hope this helps.