The soil I use should have enough calcium and magnesium in it already. But yeh, when this problem first started a couple weeks back I started adding a tsp to gallon for one of the two weekly feedings. I don't really think this is a lack of calcium or magnesium, but even adding it I am still getting phosphate lockout. Absolutely driving me bonkers trying to figure it out. But thanks for the attempt! You're the first, lol.