Update!

I just finished flushing the system with R/O water and after filling my res with 15 gal the total ppm was around 20, which is definitely within the range I want.

I then did the math to find out how much CalMag I needed for 15 gal to make 200 ppm and it came out to be .625 cups. After filling one half cup almost all the way and putting it in the res, my ppm jumped to 500! Fuck. So I added in 30 ppm of Botanicare ProGrow by doing little by little (which is what I should have done with the CalMag!!) I'm such a dumbass I then lowered the ph to 5.6 and am not letting it go above 5.9. I need much less ph down now to have an effect; I'm glad I did 3 drops at a time.

Did I just screw myself over AGAIN by putting too much CalMag into the reservoir? If needed I could go get another five gallons of R/O water from the store down the street and dilute the solution.

So, yell at my dipshit self, call me names, but please, what would you guys (and gals!) have me do?

THANKS