White sand like material in pool

[aaron07]

I have noticed in the past couple weeks a white sand Like material in my pool. I have a saltwater pool and use a rj60+ saltwater chlorinator. The pool water is clear and not cloudy. It seems to me coming out of the jets as some collects at the bottom of the hot tub below a jet. My current test results with a tf100 kit is below:
FC: 3 ppm
CYA: 40
CC: 0
PH: 7.5
TA:70
CH:250

Thank you for the help!

 

[JohnT]

What kind of filter do you have?

 

[aaron07]

Cartridge filters.

 

[aaron07]

Also I did add this stabilizer around the same time I started noticing the white material. Not sure if this could be it or not.