I added salt and the AquaRite says the salinity dropped

[Such Pool Very Swim]

I bought a house with a pool and it had a salt chlorine system. The pool guy said that the system is troubled, and he’d been managing it as a chlorine pool. He thought it needed a new salt cell. It’s a Hayward AquaRite.

I found that the flow switch wire had been cut, so I added a new connector and the flow indicator started working right. The power light wouldn’t come on, so I replaced the thermistor and now the power light comes on and when I set the switch to “super chlorinate,” the “super chlorinate”light dutifully comes on. My challenge now is leveling the salt. I have both a “low salt” and “check cell” light on.

Initially, with a broken flow switch, the AquaRite read 2900. The pool guy measured the salt around 1600 and said that the reading was probably an old reading.

After fixing the flow switch and running for a day or so, the AquaRite salt reading changed to 2100. Based on this, I added 100lb of salt (it’s a 15,000 gal pool and I’m aiming for 2900 PPM). I let it run and attempt to super-chlorinate for a day or so, and now the salt reading is at 2000 and holding steady.

I got a refractometer, but its minimum resolution is 1 ppt, and since I’m trying to distinguish in a range of 1.5-3.0 ppt, I’m not really confident in the precision of the reading.

I’m going to order Aquachek salt strips based on their reputation in the TFP forums, but I want to check my working theory of what’s going on here. Is it possible that the salt was down really low initially, and the AquaRite gave me an intermediate reading (2100) on its way down to a more accurate reading? Should I start distrusting the AquaRRite salt measurement entirely?

When we got a house with a pool, I didn’t realize it came bundled with a pool management hobby! I think this pool and I might have to just get married at this point. Every time I turn around I'm spending half an hour investigating some pool puzzle.

 

[giant_donut]

The pros here at TFP will recommend you testing with a salt test kit (K-1766) for an accurate reading of the salinity. I would start there to confirm your salt levels are accurate before adding any more salt.

 

[Such Pool Very Swim]

Thanks for the advice. Once the AquaChek strips arrived, I got a salinity reading that was pretty close to the AquaRite's, so I added salt to adjust. Today it was still a bit low, so I added one more bag and now the generator is chooching away happily. I can even smell the chlorine it's producing. My chlorine tests show a healthy range for the first time in ever.

I'm so happy I could sing. I've been trying to get this running since we moved in 6 weeks ago, and I was at a point (recovering from an algae bloom) where I thought I was going to spend the rest of my life pouring chlorine into the pool.

 

[C0d3Sp4c3]

Howdy Neighbor! Welcome to TFP
If you would like to take ownership and maintain your own pool, I'd recommend getting yourself a reliable test kit like the K-2006C or TF-100. Bear in mind, as the Salt cell gets depleted, the reported salinity reading is often lower than the actual. I use Taylor K-1766 to measure the actual salt level in my pool and go from there.
You may want to read the below to expand your knowledge about your SWCG.

Hayward Aquarite SWG - Further Reading

 

[mknauss]

I can even smell the chlorine it's producing.

FYI -- that is not good. The only thing that smells of chlorine in a pool is chloramines. That is what is left over from organics (algae) being consumed by your FC.
You need a proper test kit ------