Help !! - Water quality questions !

[flyguy1]

my current SW tank water parameters are as follows.

Nitrate 7
Phos.4 mg/l
ammonia 0
calcium 650
ph 8.3
salinity 1.023

Now the issue i am having is the new rodi water from my puratek 100 gpd system is producing these parameters

Ph 7.7
calcium 800 ppm
salinity 0 ( i have not added anything to water)

I am mixing the mass produced water in a garbage can for my water changes. I am then adding instant ocean salt and letting sit for a day before using.

fyi : my tap water without filtration is
7.7 ph
50 - calcium ppm
0 salt

Can someone please explain these and comment on my overall water parameters for my SW tank. the only thing i have dosed is some ph buffer to one garbage can awhile back. is it possible that stuff would raise all those calcium levels ? and ph ?