I think I have a mag def help me out

I'm using dyna gro in a dwc bubble just got a r.o filter today my pons yesterday was about 550 with a ph of 6.0
Now that I got a r.o filter 2day I am running a 100 ppm and ph is about 5.8
I got cal mg from go line is this shit ok for dwc
Do you think I should use it ?
Do you think I should wait to see if ph was locking out mag ?
What should I do?

Here's the pics

dump your buckets, add 3 gallons of R/o water(ppm should be around 7 ppm), put in 5 ml of grow or bloom, put in 3 ml of cal mag, and 1 ml of protekt. let it sit for 2 days and check the ph of the water. ph should be in the high fives. Even if your ph starts low thats ok. as long as it swings up by the next time you change out your water your fine.

thanks a lot I gotta order that protekt