I use 3ml per gallon. 15 ml per 5 gallon bucket. I only use it in every other nutrient mix. (I used to use it everytime, but Zandor once told me that he doesn't use it every time, or very lightly at times)

calmag is essential if you use distilled ot Reverse Osmosis water

After using all kinds of additives, I now use basically 3-part, and occasionally Liquid Karma, and calmag+.

Best thing is to mix 3-part correctly and watch you plants...they will show deficiency, and that will tell you when to use your additives.

On another note: I feel that since cutting most additives from my everyday nutrient recipe...My Pot tastes better. peace