So I had some time on my hands today Dutch and did a little more reading re MC for coco and soilless grows.
The Calmag they say is not required by most growers depending on the brand of coco, the strain, and light intensity. If you feel you need to add Calmag they recommend boosting your MC or getting a supplement such as Calmag. Bottom line is to experiment and see if you need it.
I always added it to soil once in flower, although again they say it's not needed, but my experience shows that adding Calmag during that time has not overcooked the plants and only helped in giving what the plants were looking for.
As for our supplements, well they say it's not needed (ie Bud Explosion and Sweet Candy) and is offered to enhance grows for advanced growers. Heck we're advanced growers now right???
I've never felt the need to add anything extra and after my second grow with this stuff I should be able to see a difference, if any, on my next grow when using the supplements
One thing interesting though is Sweet Candy cannot be mixed in with MegaCrop and sold together as one. High amounts of carbohydrates/sugars, so they sell it as a standalone product, but the two work fine together as separate entities mixed as one in water. So it leads me to believe that Sweet Candy should be used during flower to get the most out of the MC base nutrient.