How much more acid will I need to add with a SWG?

[jacob_coulter]

I'm giving serious thought to purchasing an SWG. I swam in someone's pool who has one, and i really do like the way the water felt. I also like the idea of less maintenance.

When I talked to a store that sold them, he indicated to me that the downside was you have to be constantly adding more acid because it raises the PH. What is the approximate desired PH level with a SWG pool? Any rough idea of about how much acid I would need to add with a 20k gallon pool?

I guess my main issue is, will I be trading less chlorine for more acid, and if so, is it basically a wash with maintenance?

 

[jblizzle]

If all you want is the feel ... then put 2000ppm of salt in your pool and call it a day.

Yes the SWG will tend to make the pH rise more, but if you lower the TA (and maybe add borates) you can greatly reduce how fast the pH actually rises. No way to generalize the amount of acid you will need.

Or, get a liquid chlorine injection system to automate adding chlorine, although you still have to haul the bleach to fill that system.

 

[jacob_coulter]

If all you want is the feel ... then put 2000ppm of salt in your pool and call it a day.

Yes the SWG will tend to make the pH rise more, but if you lower the TA (and maybe add borates) you can greatly reduce how fast the pH actually rises. No way to generalize the amount of acid you will need.

Or, get a liquid chlorine injection system to automate adding chlorine, although you still have to haul the bleach to fill that system.

Is the "feel" purely the salt in the water?

I thought some of it was the fact that there's no stabilizers with the chlorine so it cuts down on the stingy eyes/itchy skin part of the experience.

 

[jblizzle]

The feel is due to the salt.

Actually with a salt pool, we recommend running the stabilizer at a higher level (70-80ppm) than you would when using bleach (30-50ppm).

I recall a few posts mentioning more irritation when using the pucks as opposed to bleach ... maybe due to some of the additives? Or maybe the pH was getting too low? Or maybe psychological?

If you maintain all the levels at the recommended levels found in Pool School, there should be no irritation regardless of the type of chlorine used.

Eye and skin irritation is almost always due to pH out of range or high levels of CC.

 

[linen]

I thought some of it was the fact that there's no stabilizers with the chlorine so it cuts down on the stingy eyes/itchy skin part of the experience.

Most often those symptoms are caused by low ph. Properly maintained pool chemistry will fix the eyes/itchy skin issues and has nothing to do with the chlorine source.

 

[jacob_coulter]

I thought some of it was the fact that there's no stabilizers with the chlorine so it cuts down on the stingy eyes/itchy skin part of the experience.

Most often those symptoms are caused by low ph. Properly maintained pool chemistry will fix the eyes/itchy skin issues and has nothing to do with the chlorine source.

So if you had to be "off" on your PH, it's easier on the skin to have a higher PH than a lower PH.
IE, a 7.8 PH level is easier on skin/eyes than a 7.2 PH?

 

[linen]

Typically eye irritation occurs below a ph of 7.0. It can go well above 8.0 before problems. Generally, any ph between 7.0-8.0 will normally not be noticed by most people for eyes or skin. If the ph is in that range, but there is still eye/skin irritation, the next culprit to look at is the CC level. This can be tricky since it doesn't take much of the wrong CCs to irritate. If CCs are found to not be a problem, then putting salt in the water can help. See: http://www.troublefreepool.com/what-does-high-low-ph-do-to-your-skin-t24484.html#p201316

 

[Sanger440]

I guess my main issue is, will I be trading less chlorine for more acid, and if so, is it basically a wash with maintenance?

I have had a SWG for 3 years and the PH does creep up a bit, I might add 1-2 gallons a week in the middle of summer during heavy use. Very little during the winter months when the pool is not in use (still have water in it and I maintain chemicals for most part).

So I do buy 4 gallons of acid every other week to keep the PH in line. But I do not hardly every add any chlorine as my SWG does a great job. So to answer your question, I do not think that you will be lugging nearly as many jugs of chemicals if you go to a SWG.

So physical maintenance of adding chemicals is lower, but I have had to replace a couple of sensors and a cell once. So cost is a different issue than maintenance. But IMHO, the salt water is nice, the chorine levels stay good, and just adding a little acid now and then is no big deal. An my wife would never let me get rid of the salt water now, she loves it LOL!
Good Luck

 

[Ahchoo]

I guess my main issue is, will I be trading less chlorine for more acid, and if so, is it basically a wash with maintenance?

I have had a SWG for 3 years and the PH does creep up a bit, I might add 1-2 gallons a week in the middle of summer during heavy use. Very little during the winter months when the pool is not in use (still have water in it and I maintain chemicals for most part).

So I do buy 4 gallons of acid every other week to keep the PH in line. But I do not hardly every add any chlorine as my SWG does a great job. So to answer your question, I do not think that you will be lugging nearly as many jugs of chemicals if you go to a SWG.

So physical maintenance of adding chemicals is lower, but I have had to replace a couple of sensors and a cell once. So cost is a different issue than maintenance. But IMHO, the salt water is nice, the chorine levels stay good, and just adding a little acid now and then is no big deal. An my wife would never let me get rid of the salt water now, she loves it LOL!
Good Luck

I am still new at this. So I have couple question. Do you use borax in your water so you won't have to add acid so often? Also at what level do you keep your CYA? Pool school says between 60-80 but I am hesitant to raise it that high because I need to use more chlorine to achieve the same effectiveness.

 

[HotShot53]

I have a SWG, and I don't know if we just get acid rain here or something, but my PH has always been on the low side rather than high.

The higher CYA for a SWG is because it adds it more consistently, so there is usually less need for shocking etc. And the higher CYA makes the sun not burn off the chlorine as fast, so the SWG doesn't have to work as hard.

 

[Sanger440]

Do you use borax in your water so you won't have to add acid so often?

No Borax, I want to try it buy my wife likes the water the way it is LOL!

Also at what level do you keep your CYA?

I keep the CYA at about 70-80. This keeps the sun from buring off so much chlorine and allows the SWG to easily keep up (I have a big pool 20 x 40 feet) With the salt water pool I also keep the chlorine leves relatively low, (3-5) and have never had an algae bloom. The CYA level has remained constant for 3 years now, so that part is easy.

I am hesitant to raise it that high because I need to use more chlorine to achieve the same effectiveness.

As stated above, with the the salt water pool, cya at 70-80, I keept he chlorines levels pretty low and never have any kind of problems. I will dump a gallon of chlorine in after a 20 kid pool party just for good measure, but other than that, the SWG keeps up pretty well.

Obvioulsy I am sold on the whole SWG thing. I love my pool except when I have to put money in it LOL!

 

[Vickery]

I add about a quart of acid every two weeks. Vacuum once a week. Skim and scrub as needed. Borax ABSOLUTELY! That's it. Maybe an hour of maintenance a week, if that. My water sparkles and feels great. Having a pool is just so much work after joining TFP....

 

[JasonLion]

Ahchoo, CYA at 70 to 80 uses less chlorine, even though you need to use a slightly higher FC level. With a SWG higher CYA allows you to run at a lower percentage setting and your cell lasts longer than it would at lower CYA levels.

I have a SWG and have not added acid in over two years. If your fill water TA level is low, you don't have any fountains/waterfalls and you balance your levels correctly there is little if any need to add acid.

 

[mas985]

+1 to everything Jason said.

I have pretty high TA fill water (~300 ppm) and that tends to make it difficult to lower TA below 120 ppm although I found a solar cover helps to reduce evaporation and reduce the amount of high TA fill water is added to the pool. Anyway, at most I use about a gallon every couple weeks.

 

[Ahchoo]

Ahchoo, CYA at 70 to 80 uses less chlorine, even though you need to use a slightly higher FC level. With a SWG higher CYA allows you to run at a lower percentage setting and your cell lasts longer than it would at lower CYA levels.

I have a SWG and have not added acid in over two years. If your fill water TA level is low, you don't have any fountains/waterfalls and you balance your levels correctly there is little if any need to add acid.

Thank you for the info. I just finish my shocking process on Wednesday and I will start adjusting the water chemistry. Should I test my tap water to get a base reading? What kind of test do I need? TA?

 

[linen]

For tap water, I would test for ph, TA, and CH. If you want to, can also test for FC and CC to see how your municipality chlorinates.