Salt System newbie

[BigTallGuy]

Hello all. I am new to this forum so bear with me. I have a 24 foot diameter round above ground pool, with an estimated 11,500 gallons of water. I just had the liner replaced 10 days ago and had a salt system added. Based on the recommendation of the Professional Installer, I bought a Compu-pool CPSC-24 generator. Everything seemed to be going pretty well. I started with 240 lbs of salt and added another 40 lbs. to get the "Low Salt" light to go off. The local pool stores all seem to get a different salt reading, but I think I am somewhere around 3300 ppm of salt. A strange thing happened Saturday morning that I cannot explain. I was told to lower th PH in the pool as it was around 7.8. I mixed up a small amount of dry acid in its original bottle and pre-disolved it completely before adding it to the pool. I was also adding water at the same time with the garden hose. As I poured the acid into the pool at the opposite end from the skimmer, I diluted the acid with the hose. A few minutes later the low salt light came on and stayed on until I turned the unit off around noon. Later that evening the unit came on with the timer and all was well. The unit seemed to be working fine and the low salt light was out. I read later in the instruction manual that dry acid is a no-no. Could this have caused the problem? I did not use very much acid and I only lowered the PH from 7.8 to 7.7. I hope I didn't mess up the generator.

Anyway, If there is any advice that anyone wants to share I am only too glad to listen.

[CarlD]

With such a small pool I'm wondering why you wanted a salt system but that's not a problem. I hope it didn't cost you a bundle, though. Once you get it working, however, I'll bet you love it. I've never been able to cost-justify it myself but I've "kicked the tires" at least a dozen times!

If your water is 4' deep (water, not pool) then you have 13,500 gallons. To calculate volume, first use high school geometry to get the cubic footage and multiply THAT by 7.48 to get gallons. If the water is 3.5' deep then the 11,500 estimate is close.

Usually a one-time mistake like using dry acid won't do much harm, but I'm not the SWG expert here. They will certainly give you better advice.

[aylad]

I just wanted to welcome you to the forum!! My friend down the street has a 24' round Intex, and just got a SWG to put on hers. I don't know much about them, other than I want to get one to put in my IG pool but haven't bitten the bullet yet, but I'll get my hands on her owner's manual and do some investigating.

we're glad you're here!

Janet

[BigTallGuy]

With such a small pool I'm wondering why you wanted a salt system but that's not a problem. I hope it didn't cost you a bundle, though. Once you get it working, however, I'll bet you love it. I've never been able to cost-justify it myself but I've "kicked the tires" at least a dozen times!

If your water is 4' deep (water, not pool) then you have 13,500 gallons. To calculate volume, first use high school geometry to get the cubic footage and multiply THAT by 7.48 to get gallons. If the water is 3.5' deep then the 11,500 estimate is close.

Usually a one-time mistake like using dry acid won't do much harm, but I'm not the SWG expert here. They will certainly give you better advice.

Thanks for your reply. The actual water depth is 40 inches deep at the rail and is slightly deeper in the center of the pool. Call me a Wussy, but when the water warms up I'll get a more accurate measurement in the center of the pool. I actually measured the inside diameter of the pool at the waterline and found it to be 23.75 feet. Anyway, as close as I can figure, I have approximately 11,300 - 11,500 gallons.

I had a very bad experience a few years ago with Cyanuric acid and chlorine, hence the change to the salt system. I can go into deeper detail if you like. Suffice to say, I am looking forward to the break from traditional chlorine.

I was also told that most munincipal water supplies will have a token amount of salt, up to 500 ppm. I originally calculated that eight 40lb. bags of Morton Pool Salt would be required for 11,500 gallons, but 7 bags has me at 3300 ppm. The SWG booklet says 3500 ppm is ideal. I assume that there is/was a token amount of salt present upon my initial fill that would account for the difference.

Reportedly, I actually got my SWG for a steal, and there were a few things I did not know prior to the install. I will be more than willing to share my tale of woes to anyone willing to listen. But again, I am looking forward to a season of no complaints of burning eyes etc.

[CarlD]

Not necessary! (Unless it's a really good story! )

We've all been there, or someplace similar. But we can instruct you on how to make sure that never happens again. Somebody guided you wrong. CYA and chlorine are only tough if you lack sufficient info. I've used bleach or liquid chlorine for the last 10 or 11 years, and I still use Tri-chlor tabs on occasion (usually the spring), di-chlor powder on occasion, and even Cal-Hypo (but not for a couple of years now).

The KEY is regular testing and knowing what those tests mean.

[BigTallGuy]

Actually it is a good warning story for any new pool owners. I'll make it short. My TDS went off the charts a few years back and I was told to drain and re-fill the pool. The owner of the pool store advised me that I needed 4 lbs of Stabilizer for my pool. Apparently, he based his calculations on 13,500 gallons not 11,500. Anyway, I added the 4 lbs. through the skimmer as instructed 2 lbs one night and two lbs. the next night. The Pool store owner told me to bring him a sample after a week and we would adjust from there. I did this only to find out that my CYA was off the chart. It showed over 100, and was probably closer to 150. It turns out that I only needed 2-3 lbs. Here is what I learned for the benefit of all:

1) The Cyanuric acid will remain in the pool liner, pumps, filters, and other fixtures in the pool even after you drain the water out. Reducing the amount you may have to add to bring your pool to the proper level when re-filled.

2) Learn and know how many gallons are in your pool so someone at the pool store doesn't have to guess.

3) Add your chemicals slowly, about 1/2 the amount needed at a time, then get the water tested and adjust it up slowly from there. It will save you an awful lot of grief later.

[Chris1]

I'm no expert, but I’ve had a SWG for a little over five years now, so I may be able to help.... While I really believe you should pay attention to the manual for your unit regarding dry acid, you said you dissolved it first and poured it in away from the skimmer--I can't see why this should present a problem for the unit. I really think the ‘low salt’ indicator and the addition of the acid may have been a coincidence.

While I don’t have the same unit as you do, my low salt indicator will shows up (off and on) when it needs more salt. This is usually most apparent when the pool is stirred up--by swimmers, or during the addition of chemicals. It rarely stays 'on' consistently, but I always test it whenever I see it go off and then back on--it usually needs more salt (or all of the salt I've added has not yet dissolved). Whenever it gets below 3,500 ppm, off it goes. Since you said you believe yours is around 3,300 ppm, I'd suggest adding more salt to ensure the level stays above 3,500 ppm. For my unit, I’ve found that 3,500-4,000ppm is ideal. It gives me a buffer; and I've been told that you don't need to worry about equipment corrosion from excessive salt, unless it gets above 6,000 ppm.

Again, I’m no expert, but according what I’ve read, it takes 50 lb. salt per 2,000 gal. of water to reach 4,000 ppm in a newly filled pool. In future years, you will need to test before adding any salt, as the salt is only diminished by water removal (backwashing, splash out, draining). Hope this helps…

[Poolsean]

50 lbs per 2000 gallons of water increases your salinity from 0 ppm to 3000 ppm.

Most salt systems that do not have a dedicated salt sensor will provide an estimate of the salinity, based on the cell condition, water temperature, actual salt level, and the amps and volts going to the cell.
Adding dry acid that has already been predissolved, should not have caused any problems with the cell, but I'm sure the manufacturer has their own reason why they do not recommend dry acid.

If your water temperature is below 65 degrees, you should increase your salt level to the upper limit of the recommended range. This will help compensate for the decreased conductivity of the colder water.

Make sure you check your water chemistry for water balance (Saturation Index) to prevent calcium scale from building up on the blades, which will decrease efficiency and shorten cell life.

Hope this helps,

[CarlD]

That is a good story! And you should NEVER give that pool store a nickel of business again if you can help it!

Total Dissolved Solids is a problem all the time for pool stores--it's how they sell you stuff. But it is RARELY a problem for real. In fact, I cannot recall a SINGLE case in 10 years on PF where TDS was actually a problem. Besides, with an SWG, your TDS is ALWAYS high due to.......salt. Yup, the major TDS is salt. Pool store guys love to tell people that using LC or bleach will raise their TDS, never knowing that, again, the TDS is salt. You can use LC in your pool for five years and never get enough salt to run your SWG. But they'll sell you the SWG, too!

I'm sure Ben or some of the pros we have here may know of the bizarre conditions that lead to TDS being a problem, but I assure you, that ONLY happens when everything we recommend is done properly and STILL does not work. As I said, I never remember it happening.

Pool stores NEVER tell you "Only put in half, wait and have us test it, so you don't go over." They give you the wrong stuff, then sell you something to fix it, then to fix that, and that, etc. until you have spent hundreds to fix a problem that never was. Their latest routine for the last few years is phosphate levels. They even have monthly installment plans for phosphate removal. Again, I've never seen a case where phosphates were the problem--bad pool maintenance was the problem and good pool maintenance fixed it.

As I said at the top: Your problem was due to bad, irresponsible advice. Not your fault. You got "Pool Stored" as we say--and we've all been there, got burned, and learned our lessons! It's a rite of passage...

[BigTallGuy]

It seems to me if I can remember back that far that the Pool store Owner claimed the the higher the TDS reading, the less effective the other chemicals will work, and thus requiring more and more chemicals to keep the pool in check. In all fairness, it was the Pool store owner that suggested that I drain the pool rather than spend hundreds on chemicals. Don't get me wrong, I am not defending these people. When I asked them what I could do about the high CYA level, they wanted to rent me their pump for $30 per day to re-drain the pool again. They would not even let me have the pump for free even after admitting they were at fault.

After my most recent liner replacement and re-fill 2 weeks ago, I took water samples into this same store. You should have seen the look on their faces when I asked for a Salt check. I basically got the Bum's rush because they realized that their gravy train was coming to an end. So to your credit Carl, they get no mo money from me.

I have built an Excel Spread sheet to help calculate the amount of salt needed based upon the gallons of water in the pool that I will share if someone wants to see it. It is actually too large to post. So I would need to e-mail the file.

One more thing, how do I get off of the "Restricted Status"?