Salt Water Pool Conversion

[PoolDoc]

Ok. Possibilities are limited.

#1 - You added less salt than you thought, because they weren't 40# bags OR were diluted with something.
#2 - Your 'guess strips' were off . . . and so were the pool stores' strips.
#3 - Your pool has more gallons than you thought.
#4 - You're leaking and replacing a LOT of water.

I can't think of any others. If you add 160# of salt to 10,000 gallons of water, you are going to increase salinity by nearly 2000 ppm, every day of the year, everywhere in the world.

[waterbear]

a couple of thoughts:
Does your pool have an autofill and an overflow? A malfunctioning autofill can cause what you describe.

salt levels move with down CYA levels since they are both only lost by splashout, backwashing, and leaks.. Have you checked CYA to see if it is decreasing over time?

If you are using salt test strips (AquaChek) they take a full 10 minutes to develop. Most pool stores do not wait that long and the instructions on the bottle are not that clear (I got the 10 minute time from a tech note on the Hach/AquaChek website if anyone is interested in my source). If you do not wait long enough the strip, which is really a titrator, will read low.

As far as the low salt light on your unit...Your unit is reading conductivity, which is affected by more than just the level of salt in the water. Temperature, the age of the cell, the cleanliness of the cell, TDS, etc. all come into play. Chemical salt tests are tests for chloride ions (whether they are strips or titrations aka drop count tests). The chloride ion level in the water does not always correlate to the conductivity of the water. As cells age they will act like the salt is low even when it is not. Handheld electronic salt meters that some poolstores use also work by measuring conductivity. They range from very accurate if they are kept calibrated to so bad that you can get a better idea by tasting how salty the water is. My experience has been that MyronL and Oakton/Eutech meters (often rebranded as Goldline) are dependable if kept calibrated but if the store is using someting else I would not trust the results.

Finally, if you and the pool store are all testing with strips I would suspect a bad batch. Hach/AquaChek recently had a bad batch of strips that they documented on their website.

[jskins2000]

First and foremost, thank you all for your help. I am glad I joined this forum.

PoolDoc -
After you said "you are leaking water" I went out to the side and sure enough there was water coming out... I have no clue how long this has been going on, because I walk by that area often and have never seen water coming out before. Which brings in a whole new issue. When the pump is running I can see through the window of the backwash pipe that clear water running through it. Keep in mind the backwash valve is down and in the locked position. So why would water be escaping through here.

Waterbear -
My CYA is going down as well, which is probably explained by the above. The autofill is working properly. I replaced it when i moved in and it was turing / off and on as expected.

[PoolDoc]

Ah-h-h. The downside of autofill units!

I think you need to fix the leak, get fresh test strips, re-dose with salt . . . and try again.

[jskins2000]

ok thanks... now I need to see why and where it is leaking.

Does this forum give advice on beer to soothe frustration?

[waterbear]

Ah-h-h. The downside of autofill units!

I think you need to fix the leak, get fresh test strips, re-dose with salt . . . and try again.

And don't forget to get the CYA back up where it belongs (for you unit that would be 100 ppm. It is best to have the CYA at the maximum of the recommended range for technical reasons (and with your autofill and backwashing filter it can even be as high as 120 ppm as long as you maintain the FC at 5% of the current CYa level so you will need to test on a regular basis with a good test kit. I strongly recommend the Taylor K-2006. Don't get a K-2005 even though it is slightly less expensive.)
I would also look into disabling the autofill. IMHO, they create more problems then they cure. One of the biggest problems is that they mask leaks until the water bill comes in!

[jskins2000]

Yeah I am nervous about the upcoming water bill. You said, "IMHO, they create more problems then they cure." What other problems does an autofill create besides masking a leak?

[waterbear]

Yeah I am nervous about the upcoming water bill. You said, "IMHO, they create more problems then they cure." What other problems does an autofill create besides masking a leak?

Isnt that enough?
Seriously, since they are constantly adding water and most have an oveflow also (as a safeguard for when they malfunction and don't shut off--notice I said when and not if!) then it means that your chemical levels might (will) mot be as stable as a pool without one. Scenerio, 4 or 5 people in pool splashing around, water level rises and water drains out overflow, autofill adds more water, salt and CYA just went down, repeat daily. IMHO, this makes maintenance of a salt pool much harder since you need to watch the salt, CYA, and borate if you use it (highly recommended btw) than without the autofill.