I've done it using Koolbloom, both formulae (dry & liquid are different) at very low doses beginning every 10 days after flipping. I included molasses, again at very low doses, and used MgSO4 (Epsom salt) at the rate of 1g or 1/4tsp/gal, alternating with a 6% organic Ca. I learned with the FNB to start very low, I start at 2mls/gal.
I personally detest the combination Ca:Mg products. Their ratio of Ca:Mg is
too low, IMO/IME. Once I separated them, I could feed them alternately, could feed much more Ca without overdoing the Mg, which is what many plants,
especially anything that's like The White, want and need. I strongly suggest everyone who runs coir try using Ca separately from Mg, for those reasons and a few more.
1) You can ensure that your plants will never develop a Ca-. Because Ca is immobile, once detected by the grower it's usually too late, often just before the plants are ready to finish.
2) Mg- are extremely easy to correct, and it's too easy to use too much Mg because the ratios are usually 2:1 or 3:1. This ratio of Ca:Mg is too low, the lowest ratio IME/IMO is 4:1, and 6:1 is even better.
3) Once experienced, you will NEVER confuse a Mg- with a Ca- again! There is no such thing as a
Cal-Mag deficiency UNLESS the plants are deficient in both at the same time.
4) Because they're not being combined in every feed, you can push higher levels of other nutrients, including micronutrients.
I noted some differences using the old dry formulation of
Big Bud, but that had aminos in it, and everything AN can be done SO MUCH cheaper it's stupid.
You probably want to know that you'll likely be undoing, or actually killing the microbes that you're culturing if you push these chemical salts too hard. Go
very easy on them. That serves a dual.. no, triple purpose of disallowing salt build-ups to occur in the root zone, and it'll save you some scratch, too.