Oh no im not saying that the 1.3x strength is too much, my plants are just really sensitive and have always been light on feedings so I have never used that much. I just know I always end up with problems near the end if I dont flush the odd time since I always get buildups.
Definitely pick up some of that Calmag, its always good to have something and not need it, then need it and not have it.
Goodluck sir, you have a wealth of knowledge around here, im sure you'll be fine.