@ctopherl also, If you are using calcium chloride as a "Part 1" then you can add the TM Trace K to that solution. If you are using sodium bicarbonate, or even sodium carbonate (soda ash) as a "Part 2", then you can add the TM Trace A to that solution as well. That gets you from 6 solutions down to 4. By the way, there is so little of the magnesium sulfate added with the appropriate use when adding the Balling Part C, that in my opinion, it does not preclude the use of additional magnesium sulfate to supplement for Mg uptake.... Just my opinion.