Replacing chlorinator with SWG

[Dirk]

Thanks, Dirk. That helps a lot! Not sure if I’ll jump on this sale because it feels rushed, but I’ll keep my eyes peeled for a SWG deal eventually.

There are two "funds" to consider. (1) The life of the SWG, in hours that it can produce chlorine. It is exhaustible, but there are a few things you can do to prolong it. It doesn't diminish while the SWG is not being used. And (2) the life of its warranty. It is finite and there is nothing you can do to prolong that. The first fund starts to deplete when you fire it up. The second starts when you buy it...

Electronic pool equipment is running in a challenging environment. And some or all of it (depending on brand) is subject to, how shall I say, the China Syndrome (know what I mean?). SWGs are expensive. You want to be smart about how you "spend" those funds...

 

[Dirk]

There's something else to consider when it comes to adding an SWG. I cannot corroborate this, hopefully someone here can. The guys I hired to install my SWG first tested the water and determined that it would not allow the proper functioning of an SWG. I don't know what they measured, or how much of it there was, or if that was all hooey. It might have been TDS, not sure. Anyway, that's how they talked me into emptying my pool, which led to them talking me into an acid wash, which led to the complete destruction of my 6-year-old plaster, which led to the blisters, which led to my brand new pebble finish, which will lead to my lawsuit.

Point was, we need an expert here to tell us if you can add salt and an SWG to any pool and its water, in any condition, or if water can degrade to the point, or collect things to the point, that would render an SWG non-functional.

Anyone?

 

[mknauss]

You would not want to start up a SWCG pool with CH above 600, especially if you have high CH fill water. You might as well start fresh.

Otherwise, all parameters are easily managed, be it pH (very important) to CYA (add or drain some water).

You would want to be sure the pool is not full of sulfates from continuous dry acid (sodium bisulfate) use. No typical test for that, just past knowledge.

 

[Dirk]

You would not want to start up a SWCG pool with CH above 600, especially if you have high CH fill water. You might as well start fresh.

Otherwise, all parameters are easily managed, be it pH (very important) to CYA (add or drain some water).

You would want to be sure the pool is not full of sulfates from continuous dry acid (sodium bisulfate) use. No typical test for that, just past knowledge.

Well, that makes sense. Since my fill water is CH350, and the pool had never been drained in six years, my CH was likely off the chart. Maybe that's what they tested. Which would explain why my plaster was filthy with calcium, right? And my edge tile?

It's what I suspected. They let the CH get out of control. That led to the calcium build up. Which then justifies their $900 acid wash. I shudder to think that is their business model, but even if that wasn't intentional, it's no excuse for what went down with my pool.

So, MeSue, there you go. An SWG might not be in your near future, not until you replaster, or gamble on a refill. You have your kit, have you posted your test numbers? If you decide to wait on the replaster, but want the SWG sooner than later, and your current water chemistry won't support it, there are a couple ways to change it out without exposing yourself to the blistering possibility. Ones a bit tricky, the other a bit expensive.

- - - Updated - - -

Marty, just curious. Is the salt that builds up in a pool, from chlorine and acid and people, etc, the same salt that a SWG needs? Or do you have to get rid of all that other salt and use only "approved" pool salt?

 

[mknauss]

Sodium Chloride is the dominant 'salt' from all the products we use in a pool.

 

[Teald024]

Since my fill water is CH350, and the pool had never been drained in six years, my CH was likely off the chart. Maybe that's what they tested. Which would explain why my plaster was filthy with calcium, right? And my edge tile?
It's what I suspected. They let the CH get out of control. That led to the calcium build up.

Unfortunately your plaster & tile was caked with calcium due to your high CSI number. High calcium can be managed by keeping your CSI below 0.6. They let the CSI get out of control

just curious. Is the salt that builds up in a pool, from chlorine and acid and people, etc, the same salt that a SWG needs? Or do you have to get rid of all that other salt and use only "approved" pool salt?

Same salt, Sodium Chloride, common table salt. There is no "other salt" to get rid of. When buying salt, you just want to be sure there are no additives (iron, anti-caking agents, CYA, Sulfates, etc....) You would be surprised what some companies add and call it Pool Salt Water Generator Salt. Any local hardware store or big box store (blue, orange or green) should have granular salt. It may come under different labels with different prices. Some call it pool salt, solar salt, softener salt. Look for the 99...% purity NaCl. What ever is cheapest pure salt you can find. Doesn't have to be pool salt, just pure salt. The smaller the granular, the faster it will dissolve.

sorry for the thread hijack. Back to the OP topic. :gone:

 

[domct203]

I use the Morton Solar Crystals, marketed for water softeners, easily available at any big-box hardware store, and not expensive at all. It's over 99% pure and I've never had an issue.

https://www.lowes.com/pd/Morton-40-lb-Salt-Solar-Crystals/1039111

When I need to add the salt, I like to do it with the kids in the pool. We play 'diamond hunt' and the one who comes up with the biggest 'diamond' each round wins! This will really help dissolve the salt.

 

[MeSue]

So, MeSue, there you go. An SWG might not be in your near future, not until you replaster, or gamble on a refill. You have your kit, have you posted your test numbers? If you decide to wait on the replaster, but want the SWG sooner than later, and your current water chemistry won't support it, there are a couple ways to change it out without exposing yourself to the blistering possibility. Ones a bit tricky, the other a bit expensive.

My numbers are pretty good, though I haven't tested for metals or anything other than what I can test with the TF test kit. The CYA was high, but not as high as I imagined it could have been.

I got CYA down to 80 last check.
Dumped a lot of liquid chlorine in and have been letting it fall back down to recommended maintenance level. (last check it was 14)
CC has been under 0.5 for several weeks.
pH: 7.5
TA: 90
CH: 330
Borates: 50

 

[Dirk]

I'll leave the water balancing advice to others here, but it looks to me like you have some options available, without having to empty much or any of your water. Without seeing your pool in person, or examining close up the plaster issues, my gut, and if it were my pool, I would not empty the pool to patch the plaster. I wouldn't take the risk of blistering. If I could live with the plaster glitches, and needed to put the replaster job off a year or more, I'd make sure my pool passed a leak test and I'd add the salt (following TFP advice about it) and the SWG, tweak the balance a bit, and call it a day. If the tile issues were bothering me enough, and if balancing required replacing a bit of your water, I'd drain the pool down the required amount (talkin' inches, not feet), and use a few tricks to repair the tile, then refill as quickly as possible. If the plaster was bugging me, or if the leak test fails, I'd hold off on the SWG and bite the bullet and remodel, then add the SWG a month or two after the new surface cures a bit...

 

[cfherrman]

Your fc has to be under 10 for the pH test to work.

 

[MeSue]

Your fc has to be under 10 for the pH test to work.

Yeah, that was my last measurement when it was under 10. Been waiting for it to get back down to test again.

Good, thoughts Dirk. A leak test is a good idea. The plaster issues aren’t bothering me and I’d just as soon save up for a remodel a few years down the road if it’s possible to postpone. Fingers crossed...

We sure have been enjoying it so far. Never thought I’d be swimming in February!

 

[needsajet]

Yep, if you patch the plaster, the patches just show up, which a friend here pointed out to me, so I'm glad you came to a good conclusion, for now as you say, that works for you.

So with no draining to worry about, are you going to order an SWG?

 

[MeSue]

Yes, I think so. It’s a good idea to do a leak test first so I need to do that and let my husband finish some more pressing projects before I add one more to his list.