Using cal mag properly

Grow Cycle
1

I’m sure it’s in a previous topic and I did try to see but did not do well in reading so I’ll ask Should I use cal mag when just watering between feeds and should I use cal mag when I’m flushing?

2

A lot of growers add cal mag alongside when feeding some add it when not feeding.
I add every time.
Flushing I would add it the next time I fed.

3

I add every time too… I also add liquid bone meal and Epsom in every time (both tiny amounts)