No chlorine in salt water pool! Test positive for phosphates and nitrates

Jul 19, 2014
3
New Hampshire
Because my salt water pool was not producing chlorine, the pool store tested the water for phosphates. It said it had 300 ppm. They sent me home with a phosphate remover. I waited 72 hrs and back washed the DE filter, even though the pressure never went up. I brought a sample in again, and this time there were 500 ppm!!! He had me double dose the pool with a remover. Pressure never rose, but backwashed as indicated. Phosphate level remained at 500ppm!!
They tested for nitrates. It came back at 26 ppm. I was told to empty the pool water down to a foot in the low end.
Do I have to??!!! Is this the only alternative?!! I have a month left before we close the pool for the winter. I would hate to pay for new water and salt, only to drain the pool again in a month for winter!!!!
Help please!!
 
Welcome to TFP!

Neither phosphates or nitrates matter. Both are algae food, but if you have chlorine in the water the algae will all be killed regardless.

Most SWG problems are caused by chemical levels being out of balance. Could you post a complete set of test results?

It is also possible there is a hardware problem of some kind. Do you have any error lights or error messages on the SWG?
 
Because my salt water pool was not producing chlorine, the pool store tested the water for phosphates. It said it had 300 ppm. They sent me home with a phosphate remover. I waited 72 hrs and back washed the DE filter, even though the pressure never went up. I brought a sample in again, and this time there were 500 ppm!!! He had me double dose the pool with a remover.
Wow. When the test results didn't make any sense, he just doubled down. Ignore the phosphates and get a proper chlorine to CYA ratio and you'll do fine. While I wouldn't trust their results, what are your stats? Especially that CYA/stabilizer?

It would be good to get your generator going, but I have no advice on that. I don't have one.

While it will take a bit of reading to get up to speed, you can just add liquid chlorine (aka bleach) for a month until close. If you're going to drain anyway, you could probably use trichlor pucks. The build up of CYA won't be bad in one month. The point is, you have lots of alternatives, but you'll need to read up in "Pool School" to understand them.
 
From those test results I will offer this:

1. The cyanuric acid level is low and the sun is burning off the chlorine.

2. Algae has started and the SWG can not make enough chlorine to get ahead of the algae. The chlorine is used up killing off the algae before it registers in the pool. It is very common that SWG users do not see visible algae as the SWG is making just enough chlorine to prevent the algae from blooming.

You do not need to drain the pool, but you do need to go through the SLAM Process. Please read the following links and ask questions if needed.

http://www.troublefreepool.com/content/123-abc-of-pool-water-chemistry
http://www.troublefreepool.com/content/127-salt-water-chlorine-generators-swg
http://www.troublefreepool.com/content/125-slam-shock-level-and-maintain-shockingl
 
Welcome to the forum :wave:

Those pool store numbers just don't seem right. I don't think they can test accurately to .01 ppm in chlorine or 5ppm in CYA. Most test kits have 20 as the low limit on the CYA test and most FC is red in .5 increments.
 
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