balling, dosing, etc...

[Emeraude1484]

I need to start dosing. I've decided on the balling salts from Ocean Fresh Aquatics (had to keep it in Canada ) I'm trying to figure out 2 things the mix itself in a gallon of RO water and dosing itself...
day of water change Parameters on 26th were:
DKH:9
Calcium:420
Didn't have a mag test

24hrs later:
*DKH:7* lowered from 9 in a day
Calcium:420
Mag: 1200

Will be dosing manually for now.
Can anyone please chime in about my measurements here just so I can make sure I don't schock anything.

CA- 1.5cups/gal
KH- 1cup,1tsp/gal
Mg- 1cup mag chloride + 1tsp Epsom/gal

As for when I dose... Is this calculator alright or does someone refer me somewhere else?
http://reef.diesyst.com/chemcalc/chemcalc.html
Thanks!
Stef