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View Full Version : I think I want to go salt.



estermer
04-01-2006, 08:09 PM
I have a 25K gallon in ground pool with a black pebble tech finish.

Living in Southern California, it is very common for my pool to reach 90 degrees during the summer. Between the temp and bather load, during this time I use a significant amount of chlorine. I have an inline chlorinator which is set to full and I regularly dump about 1 pound of granules every few days to keep it chlorinated.

I am interested in converting to salt. Do you think it would work in my situation? I generally run my filter for 5-6 hours per day in the summer.

Thank you

SJohnson
04-01-2006, 10:36 PM
If you go by the opinions on this board, there are two swc's at the top of the list, the AquaRite by Hayward/Goldline or the Autopilot Salt System. They are both very good products and effective chlorine producers. Since you have a high chlorine demand, you may want to go with an over-rated Autopilot SaltWater Chlorinator. There is only one version of the aquarite, as far as I know and it is rated to supply chlorine up to 40,000 gallons, whereas the autopilot has three versions, the Pool Pilot Digital Super Cell 36, 48, and 60 with the 60 being rated for pools up to 50,000 gallons. If you think your chlorine demand is that high, you may benefit from the 60. The AutoPilot also has more bells and whistles, such as an automatic water temperature adjustment, that adjusts the output based on water temps, with more chlorine produced in summer, less in winter, etc. I went with the aquarite because I am getting the aqualogic control system by hayward/goldline, so it just seemed easier for me. If I were converting to salt and just needed the swc, I would have gone with the autopilot. Both are good, I think, and I researched this extensively . . . Can't go terribly wrong either way . . . the trick seems to be generating enough chlorine based on your pump runtimes and in six hours, you may want to get something that has the output you need. It should work great for you, just remember to shock with bleach to save your cell life . . .

Links:
AquaRite: http://www.goldlinecontrols.com
AutoPilot: http://www.autopilot.com

Hope that helps you,

-SJohnson

CarlD
04-01-2006, 11:50 PM
I'm afraid SJohnson has missed the obvious reason for your high chlorine demand. It's SO obvious that it's smacking me in the face.

You are using an in-line chlorinator with Tri-Chlor pucks. Tri-chlor adds CYA (Stabilizer) to your pool. The higher stabilizer goes, the more chlorine you need to keep it sanitary. I'd bet the rent you are well north of 100ppm in CYA.

What you need is to get a posting of your test numbers:
FC
CC
pH
CYA
TA
and CA

Get yourself a test kit that tests these--Ben, and Taylor have kits that measure FC up to 50 or 100ppm--you need it.

If I'm right (and I probably am), you need to STOP USING PUCKS! Use Liquid Chlorine (Sodium Hypochlorite solution)--the supermarket sells it in bottles marked "Laundry Bleach". You probably need to keep your daily chlorine level between 8 and 15ppm.

Or, you can dump a good portion of your water and refill. If your CYA is 120, and you dump half your water, it will now be 60ppm. 60ppm is normally a tad high, but in constant 90+ heat it will slow the environment (UV and heat) from consuming your chlorine. You want your chlorine consumed getting rid of contaminants--suntan oil and algae.

There's nothing wrong with SWGs--they work great--but they are expensive and so are repairs--that buys an awful lot of bleach. I figure a properly maintained pool will use 45-90 gallons a season--at about $1/gallon. A $900 system is 10-20 years of bleach! Still, if you need the convenience, like to successfully run at lower chlorine levels, and like the feel saltwater gives, an SWG is for you!

But I suggest you first get to the REAL root of your heavy chlorine demands--almost definitely a pool super-saturated with Cyanuric Acid--CYA/Stabilizer. THEN, once that's not an issue, decide on an SWG, rather than throwing money at the pool and hoping it fixes it. It won't, until you get CYA levels down.

I test my water every day--takes 2 minutes with practice. If chlorine is low, I pour a jug of bleach into the skimmer for a total of 3 minutes a day. That's why I can't justify an SWG. For me, it saves me next to nothing.

waterbear
04-02-2006, 12:03 AM
Aslo, the aqualogic can be used with bigger pools by wiring an aquarite into the control panel but if I am not mistaken one cell can handle a pool up to 40,000 gal.

SJohnson
04-02-2006, 01:47 AM
CarlD's probably right, in fact I'm positive you'll find your cya levels are off, either too low or way too high. I just assume everyone knows this stuff . . .

SJohnson

mwsmith2
04-02-2006, 06:21 PM
I'm afraid SJohnson has missed the obvious reason for your high chlorine demand. It's SO obvious that it's smacking me in the face.

Mmmm, I'm not so sure. He doesn't report an algae problem, so I'm thinking the trouble is keeping Cl up high enough to keep the pool sanitary, not keeping algae down.

A 90 degree pool + lots of sun + lots of people = lots of cl demand. I think a SWC will be able to do it, but i'm thinking your pump run time may need to be adjusted to 8 hrs, to give enough time to turn the pool over properly and also give time to make Cl.

Michael

SJohnson
04-02-2006, 11:00 PM
How about you test your cya and post it, then everyone can give you some good, accurate advice . . .

SJohnson

hzz
04-03-2006, 06:03 PM
Just to add to what Michael said...I also think a SWG will work for you....just be sure you oversize it for your situation.

If you go for the Autopilot get the 60 cell....I got that one for my pool even though it is a bit of overkill.

CarlD
04-04-2006, 10:56 AM
OK, let me be clear:

It's not that the thread-starter cannot use an SWG--I would never say that or imply that. But if he is having a problem with his water, throwing money at it by adding expensive stuff probably won't solve it. You have to solve the problem first. There's no way around that.

waterbear
04-04-2006, 11:09 AM
Mmmm, I'm not so sure. He doesn't report an algae problem, so I'm thinking the trouble is keeping Cl up high enough to keep the pool sanitary, not keeping algae down.

A 90 degree pool + lots of sun + lots of people = lots of cl demand. I think a SWC will be able to do it, but i'm thinking your pump run time may need to be adjusted to 8 hrs, to give enough time to turn the pool over properly and also give time to make Cl.

Michael
I tend to agree. A SWG would make maintaining the Cl levels as close to automatic as you can get. Just got to tweak the pump run time and Clorine generation output of the cell. Not rocket science at all! Just takes testing of your levels until they are correct and holding. The plus side is that the need to shock will be greatly reduced or elimiated once it is all adjusted properly.

estermer
04-04-2006, 06:16 PM
Here are my test results.

Free Chlorine 3.0
Total Chlorine 3.0
PH 7.6
TA 110
Calcium Hardness 270
CYA 30
Total Disolved Solids 650

Poolsean
04-04-2006, 07:46 PM
Looks like a case of low cyanuric acid ??!!? Tri-chlor tabs being used and low cyanuric acid? Very Interesting!
Any chance your pool having an Automatic Water Level device and perhaps a leak somewhere?

If not, it's possible that your low cyanuric acid is allow the sun's uv rays to degradate the chlorine.
You can use a Salt Chlorine Generator, but as with very wise recommendations, you're better off upsizing the cell to the largest one you can afford. This should provide a higher chlorine output, longer warranty, and longer cell life.

SJohnson
04-04-2006, 08:02 PM
If there's a leak or constant refilling, wouldn't his total dissolved solids be lower??, 650 seems a little high to me . . . I say bring your CYA up to at least 60 before you install the SWC. Triclor use with low CYA levels, hmmm . . . something's not right with this picture, I agree . . . All those numbers look exactly where you want them to be!!

You're not using Calcium Hypochlorite are you?? You did say, "I regularly dump about 1 pound of granules" . . . That would explain allot, but I didn't think you were supposed to use that with in-line feeders . . .

SJohnson

estermer
04-04-2006, 09:04 PM
Well the water in the pool has only been in it for about 10 months. I have also backflushed my filter twice since then and had to drain off some after a heavy rain.

The granules I put in is Sodium Dichloro-s-triazinetraine dihydrate and I put it directly into the pool.

What is the optimum level for CYA for a bleach pool and for a Salt pool?

SJohnson
04-04-2006, 11:10 PM
Is that the same as sodium dichloroisocyanuric acid?? Anyway, the accepted levels for a "bleach" pool are around 30-50 ppm. Where the Salt Cell manufacturers recommend 60-80 ppm, I believe. Again, some on this site keep their levels much higher, say 120 ppm, with very high levels of chlorine to offset the conversion of chlorine to chlorimide, or chlorine lock, where the chlorine no longer is actively disinfecting the pool water. PoolDoc(Ben) wrote somewhere that high levels of CYA could be considered a good thing, where it preserves your chlorine longer and prevents it from being burned off in the sun. This way you don't have to add chlorine as often . . . it had something to do with the chlorine's reaction time to bio-bugs in the water. The downside being that highly stabilized chlorine has a slower reaction time than chlorine with lower levels of stabilizer in the water. I think he said high stabilizer levels kept the chlorine in reserve and released it as needed, but the time it took to release the chlorine added to the chlorine's disinfection reaction time . . .Something like that, I remember the article or thread was a very interesting read, wish I could track it down, but it may have been lost when the board crashed . . .

Hope this is helping you, I think you just need to bump up your cya levels a little . . . the debate is ongoing about cya levels and where they should be, everyone seems to differ on that subject a little.

-SJohnson

SJohnson
04-04-2006, 11:20 PM
Wait a minute . . . You said that you have an inline chlorinator and you add granules every few days? You put trichlor tabs in the feeder and are dumping dichlor granules in the pool directly? Is that right? CYA levels are usually very stable so minimal draining and backwashing will not lower it all that much. Hmmm. Did you test the CYA or did a pool store test it? That kind of Dichlor your using is 56% chlorine whereas Trichlor is 90%. 1 lb of Dichlor should raise your chlorine level about 3 ppm, in summer heat, direct sun, every 3-4 days, that doesn't sound all that unreasonable . . . you're gonna love the Salt Cell . . . I'll bet.

SJohnson

Poolsean
04-05-2006, 01:42 AM
SJohnson, 650 ppm TDS is not too bad. Most tap water is really low, about 100 ppm. I would say that 10 months of tri-chlor and di-chlor, both of which adds salt and cyanuric acid to the pool, would have increased the cya level and salt level higher. The backwashing and rain water drain off, would account to a lower level, but a leak would certainly lower these levels much more than normal.
However, since there was no response about an automatic water fill line, or any suspicions of a leak, there probably isn't one. OK...so back to what is consuming your chlorine at a higher pace than normal. One should not need to have a tri-chlorine erosion feeder AND have to hand dose di-chlor.

Have you added anything other than chlorine and acid to your pool? Take that back, since tabs and di-chlor are both low on the pH scale, no need for acid, but perhaps some soda ash, to increase pH. Any algaecides, clarifiers, or additives? If so, these may be reacting with the chlorine added and just plain and simply, using up the chlorine.

estermer
04-05-2006, 02:01 AM
The only chemicals that have ever been in my pool in addition to the two forms of chlorine already mentioned are Acid, borax, and bleach. After the initial acid washing and needing to raise the PH, chlorine and acid are the only things I need in my pool. My PH creeps up and I usually need about 1/4 to 1/2 gallon of acid per month to keep it at 7.6.

As for an automatic water line, yes I have one. Although it is possible that I have a leak, I really doubt it. We had some heavy rain last week and it filled the pool up. A week later, it's still very full and I know the auto fill hasn't kicked in. When I first had the pool remodeled last year, I quickly spotted a leak as the fill line was almost always on and the water level would drop pretty fast.

So I am thinking that I need to up my CYA to at least 50 and then look at the Autopilot 60.

scoobiedoob
04-08-2006, 12:46 AM
Our pool is similar in size to yours, maybe 2000 more gallons. We got our Autopilot 60 last year and love it. I can't say it will be the same for everyone because it appears there are a lot of factors, but it has been a breeze to maintain our pool since we got it. The water stayed beautiful all winter long and since we've had it we've added a total of about 2 gallons of acid and maybe a few cups of clarifier just for good measure. All testing has been excellent with the Pool Solutions test kit, which is a fine kit. We just added a 150 lbs of salt for the beginning of the warm season along with a few lbs of CA. I checked our cell the other day and it still looks brand spankin' new. I can't speak highly enough about it... best move we've made for convenience and ease of pool care.

CarlD
04-08-2006, 11:23 AM
OK,
I'm a bit confused: Your numbers look EXCELLENT!

I have no idea why anybody worries about TDS--it has little if any effect on your pool--it MIGHT indicate the presence of metals--but they should be tested for separately. You already have a good calcium and total alkalinity number.

I have no idea why PoolSean thinks your CYA is low at 30ppm. I might consider going to 40 or 50 ppm given your conditions, but I do not like going higher. Your FC is FINE for 30ppm

The only baffling thing is if you are using tri-chlor tabs in a feeder and di-chlor powder to supplement, why is CYA only 30? This has been picked up by the other posters.

There are only two possibilities (also noted by others):
1) You have a leak and are re-filling all the time such as by an auto-leveler (they sound so complicated but they work just like a bathroom toilet's float valve--that simple)
2) Your pool store tested wrong. Could they really do that?????? Well, yes. You can get more accurate numbers from the $15 WalMart HTH 5-Way test kit (if you can still find them in your area--long gone in mine). And, of course, from Ben's kit or the Taylor kits. I suspect your CYA is much higher.

Someone said Ben recommended higher CYA levels. That's not exactly right. Ben HAS said there is no problem with running higher CYA levels as long as you follow the rules of keeping your FC at the approriate levels, and you might see less see-sawing of FC.

But everyone seems to forget that Ben has also posted another article showing that the advantages of higher CYA levels fall off dramatically once you get much above 25-30ppm--you don't protect chlorine much and you lose effectiveness...So which is true?

So I generally aim for 30, and if like the originally poster, I am in for weeks or months of plus 90 sunny weather (and, yes, we get that in New Jersey--my backyard frequently hits 100 by mid to late May), I may run CYA to 40 or even 50, especially if I seem to use a lot of chlorine.

But you have to be careful--despite doing that last summer I had a minor algae bloom--the first in this pool and the first in years. I hammered it 3x a day with FC levels of 15-20ppm and in 24 hours it was gone, and in 48 I was back to normal. I was annoyed and annoyed with myself...I broke my own rules and paid for it.

Beautye350
04-09-2006, 11:42 PM
I am trying to decide between the autopilot and aquarite setups for my pool. I like the idea of the integrated automation of the autopilot (I would love for the system to automatically turn on the pool pumps when needed to sanitize, etc...), but I have a concern as to their pre-assembled manifold. I have not seen in their manuals or mentioned anywhere else if the manifold can be mounted vertically? Does anyone know if manifold orientation makes a difference on that unit? The aquarite manual, on the other hand, shows vertical installation as being possible (which is the only way I can do it on my setup without getting super crazy on the piping)? This alone may make the decision for me. Thanks.


Regards,

Mark

EDIT: I'm thinking I wasn't clear enough so I will try and explain a little better. My return line exits the top of my Hayward EC65 and goes about 3 inches into a coupling (so I can easily remove the filter from the system) and then takes a 90 degree turn and goes straight down into the ground. I can only place the generator cell or manifold in that downward piping. I hope that helps explain a little better in case I wasn't clear before.

Poolsean
04-10-2006, 01:11 AM
Beautye,

You're fine installing the manifold assembly this way. Hope this helps you with your decision and thanks for considering AutoPilot.

Beautye350
04-10-2006, 07:48 PM
Not that I am doubting you, but after I posted my question here I did some more research and came across this statement in the "Digital Total Control Manual.pdf"


The manifold/cell should be installed in a vertical orientation as illustrated in the picture below. This orientation
prevents hazardous gas buildup in the system if the flow switch should fail to detect insufficient flow.


http://home.comcast.net/%7Eflyinz28/manifold.JPG

I definitely don't want to create a hazardous situation here. Still stand by your statement that I can install it in a vertical running pipe? Thanks for your assistance.


Regards,

Mark

Poolsean
04-11-2006, 09:42 AM
Definately. We want to avoid mounting the manifold upside down (with the manifold loop below the horizontal base. You can mount it vertically as you described.

Beautye350
04-11-2006, 02:37 PM
Great! Thank you. I appreciate your help.


Regards,

Mark

hzz
04-11-2006, 05:28 PM
That manifold is one of the things that sold me on the Autopilot. I like the idea of the check valve, on my system it seems to bleed off a lot of excess pressure.

Without it I am not sure how you could regulate the water pressure through the cell.

Anyway, good luck with your decision. Whichever way you go you will be happy with your SWG