salt test discrepancies

[Jonsstihl]

I used 40kg of salt to raise my pool 1000ppm of salt

my dad used 40 kg of salt to raise his pool by 1000ppm

the only problem is that my pool is 10,000 gallons and his is 15,000 gallons

how is that possible. I'm using the smart stir with the test and I do stop before it turns brown.

 

[AK-]

What was the starting point for both pools? Did the same person did both tests with the same test kit?

40Kg of salt on 10K gal = 1054 ppm
40Kg of salt on 15K gal = 703 ppm

K-1766 precision (drop) 200ppm

I suspect good part of the difference is due to the test tolerance on each pool or even a small mistake in on of the initial test (plus/minus one drop would account for most of the difference).
How well dissolved the salt is and the pool circulation can play a part too.

 

[Jonsstihl]

mine went from 2200 to 3200 and I just tested it again and I got 3400

my dads went from 1400 to 2400

I did both tests with my test kit. I am having trouble convincing them to use the TFP method. They still believe the pool installer that told them to put one 20kg bag of salt in then start the salt cell. you should have seen the look on their faces when I told them they needed 4 bags of salt.

It may be a little bit of both, testing inconsistencies and salt not dissolved. they put the one bag in the day before I tested he said he brushed it after but... The turning point of the test is very obvious but the volume is where the discrepancies are easy to get.

so it is almost like they lost all their salt over the winter. Last summer was the first year and they put 5 bags of salt in. pool was not drained at all over the winter but did have a lot of leaf debris in it.