Startup SWG chlorinator salt for new pool

[mgtfp]

just to mention i was at my local pharmacy spoke with the owner and he said he has the same swg, owned his pool for many years, i mentioned how i am testing to get it right, he looked at me strangely and said why, all he does is put in salt, he could not understand why i had to test anything, i mean anything ! he does no testing, i asked again really nothing, how about a service guy that comes out, nope, all he does is put salt in, never had any issues, i mentioned in winter about adjusting output, nope he does nothing, this guy is a very switched on guy and i have known him for many years , so its not some story, i just dont get it, i can only assume his swg is set reasonably high to cover all issues and is just set that way all year...but that still dont take care of PH, TA, CYA etc....i will question him again next time as it just dont sound right.....

Hmmm, I would have thought that a pharmacist might be a bit more interested in chemistry, and making sure that his water is actually safe to swim in...

 

[Dirk]

Most pool owners don't know what they don't know, let alone what they should know. Ya know?

 

[Newdude]

#preach !!

 

[mgtfp]

Most pool owners don't know what they don't know, let alone what they should know. Ya know?

Sounds a bit like Dunning-Kruger...

 

[Dirk]

I had to look that up. I've always felt I was somewhere near the peak. I never realized there are two!

 

[mgtfp]

Great graph, haven't seen that one before. I particularly like the fact that there are stick figures getting pushed "up" to the first peak - i.e. they decrease their level of expertise to increase their confidence. Isn't that the typical "career" path in many large companies?

 

[Dirk]

Great graph, haven't seen that one before. I particularly like the fact that there are stick figures getting pushed "up" to the first peak - i.e. they decrease their level of expertise to increase their confidence. Isn't that the typical "career" path in many large companies?

I hadn't heard of that phenomenon before, but I've certainly had to deal with all types along that arc!

 

[FIESTA62]

hi, well i guess by now you have heard enough about my FC testing , but i have another question..... as winter is on the way there will be less FC burn off from UV, but i assume i need to keep FC up to target at a least minimum, but what about CYA? right now i have 70 cya, target 5, but i am keeping it at 7

so during winter do i still keep at 7, i assume so, but do i also keep cya at 70 as UV is less, i would rather just keep at 70 just to keep things easy no change etc, but is 70 too high for the winter months

on the FC testing i have had a penny drop moment yay, i know u all told me this but now i really get it, i was testing 50% at 6 hours but it dropped 0.5 FC each day for 3 days so 50% at 5 hours was not working, but i know 50% at 5 hours produces 2.5 FC using effects of adding, but i was losing the 0.5 FC

i checked math and see 75% at 5 hours produces 3.1 FC, so i get 0.6 more which should be spot on, i know its just a guide but " effects of adding " is much better than me just guessing, so i started a new test run, 75% / 5 hours......

 

[wireform]

If the water temp drops below SWCG minimums then you forget about the CYA till next season. Keep the FC at 3 and it shouldn't move that quick. Are you winterizing pool then you will need to bring FC to slam level before winterizing.

 

[FIESTA62]

water temp drops below SWCG minimums

hi, well i didn't know there was a minimum swg temp, and i don't know much or really anything about winterizing but i think that's done in areas of extreme cold, i am in Australia on the beach's it don't get very cold here, in the peak of winter its too cold for swimming but its not snowing !

 

[Dirk]

If your SWG throws a "too cold" alert of some kind (mine is a red LED) then your pool technically becomes a non-swg pool and you can safely ignore CYA until the Spring. Personally, I still use the same FC level all year round. My actual minimum is 3, and the low-end of my target is 5, but I still treat 5 as my minimum. I go to 7 on Mondays and then let it drift down for a week, to whatever it gets to. Which honestly is sometimes less than 5, but never less than 3. Once it starts to warm up again, the SWG comes back on and then I'm much more strict with my "pretend" minimum of 5.

If you SWG stays on all year, then you use the same number all year, for both CYA and FC.

 

[mguzzy]

Most SWGs have a cut off and will display a warning when the water temp is below 50 deg F (not sure what that is in C). As the water temp decreases the SWG output decreases, at least for mine. In the winter my pool hovers just below 50... and it stops producing. And with the sun hitting the pool at a lower angle there is less effect of UV degradation on the CL. So the CYA is not really needed as much. Plus the lower temps suppress the bio activity of the algae, but it doesn't completely stop it. So I just maintain my target FC.. and I find it takes less chlorine to do it. As the temp decreases, so does the FC output of the SWG.. but I don't need as much to keep it there.. its kind of self-sustaining until it gets cold enough to hit the SWG shut off threshold. For the three coldest months of the winter (Dec, Jan, Feb for us) I have to manually dose with liquid chlorine.. but it doesn't take much. Then come spring I start adjusting the CYA and other levels as things start to warm up and the sun gets higher in the sky.

@Dirk and I are in the same area.. so we experience the same seasons. If you are at the same latitude but south your seasons should be about the same as ours just reversed on the calendar.

 

[FIESTA62]

less effect of UV degradation on the CL. So the CYA is not really needed as much.

my swg does not have a cold water alert minimum, so it will run all year unless i decide to manually dose , ok so my actual pool math target is 5, but i aim for 7 but from what you all said winter months needs less CYA and pool is less likely to get Algae, so i can relax a bit on aiming for FC7 and if it goes down to pool math target FC5 no big deal but keep it above the minimum of FC 3

 

[mgtfp]

my swg does not have a cold water alert minimum, so it will run all year unless i decide to manually dose , ok so my actual pool math target is 5, but i aim for 7 but from what you all said winter months needs less CYA and pool is less likely to get Algae, so i can relax a bit on aiming for FC7 and if it goes down to pool math target FC5 no big deal but keep it above the minimum of FC 3

My SWG runs through all of winter, water temps go down to about 8°C, my SWG doesn't have a cold water shut down feature. That's in Melbourne, I assume water temps in Sydney stay higher.

I let my CYA come down in autumn, but I don't let it drop below 30, because below that the test doesn't really work anymore, and I prefer to know where I am. And as long as there is at least some CYA in the water, it is very hard to actually over-chlorinate, whereas with CYA 0, you don't want to be above FC 3ppm. If CYA drops below 30ppm, I just add 10ppm worth of CYA, that keeps it in the measurable range. It also helps to definitely have some CYA left in spring, it can go very quickly from hardly no chlorine demand at all to burning off everything in a day if there is no CYA at all in the water. Once spring comes, I bump CYA up to summer level again.

I stick to my target FC for the current CYA level all year round. But I do let FC rise a bit higher in winter. UV-loss is so small in winter, that doesn't really create unnecessary chlorine losses, and it gives some extra buffer when testing only weekly or even less. That buffer is usually much appreciated in spring, when FC can start to drop very quickly. I have a very sharp transition between full sun on the pool, and a lot of sun being shaded off by trees and fences. As quickly as my chlorine demand is starting to drop now, as quickly it will rise again towards October.

 

[Dirk]

Well, you two are no fun. Nothing left for me to advise!! Both posts right on!

mg brings up a good point, and one I live by. Keep the FC up all winter as if it's already spring. You never know when that spring day will hit, and a pool can turn green pretty fast with an unexpected perfect-storm combination of: warm temps, extra sun, throw in some pollen, a little lax on testing and boom. GREEN!!

I gotta say, I'm not feelin' too sorry for you guys with your approaching cold season. Because for your northern brothers and sisters, that means:

 

[mguzzy]

My SWG runs through all of winter, water temps go down to about 8°C, my SWG doesn't have a cold water shut down feature. That's in Melbourne, I assume water temps in Sydney stay higher.

I'm pretty sure all SWG's reduce FC output in cold water, whether they tell you that or not. Its a function of the electrolysis reaction and it helps protect the cell I remember reading somewhere. (Out of curiosity I pulled up the Watermaid SWG manual, and your right there is no mention of a cold water shut off as in other brands). Anyway, just like others have said, I would keep your target from the FC/CYA Levels as your minimum, that way if something happens you have a buffer. Remember it won't hurt it to have more as long as you are below SLAM levels. And in the winter it will take less liquid chlorine to maintain your target FC, whatever it is, than in the summer with higher temps, greater bather load and more direct sun. During my winter months when the SWG was off, I only used 3 gallons.

 

[FIESTA62]

ok i get it i will keep FC at 7, minimum 5........ but you know i always have trouble with cya testing, i did a test a few weeks ago, used Taylor test and then a Clear choice test, really trying to nail it, took my time made sure i got it right and called it 70, today i test just 2 weeks later and get 40 possibly 50, i am calling it 50, in 2 weeks i go from 70 to 50 , i seem to have put a lot of stabiliser in over the past months, autumn is here but i expect some warm weather to be around for a bit yet so i will put a bit more stabiliser in to bump it up to 70

 

[Dirk]

CYA does degrade over time, but not like that. And it doesn't evaporate. You're either getting a lot of water exchange, like a whole lot, from rain or splash-out, or it's testing error. Just do the best you can. I like to repeat the test, by pouring the first test sample back into the squirter and then squirting back into the graduated vial. I do it at least three times, until I keep getting the same result...

 

[FIESTA62]

repeat the test,

i repeated at least 3 times more like 6, from all angles, inside outside etc, and after all that i came to 70....strange i know, i seem to always have trouble with cya tests, i ordered new regent today so will test again when it arrives....anyway pool is sparkling so whatever it is its working...

 

[Dirk]

Well, I hate the CYA test. It's the only one that makes me feel like it's just a best guess. But you're on the right track. The pool is the ultimate confirmation that you're either doing it wrong or right. If your FC holds reasonably well from week to week, and you're algae free and crystal clear, then you've got a good amount of CYA!