I found this CalMag with vitamin C supplement, one of those powder in water deals, and I was wondering if it would be safe to use once in a while mixed with the plant's water. Maybe even add it to my supersoil? The ingredients are as follows: the nutritional facts say Vitamin C, Calcium and Magnesium, then other ingredients: calcium glucinate, citric acid, magnesium carbonate, ascorbic acid, and unsweetened lemon juice. I thought it may help. I know vitamin C is a good antioxidant for plants and help with stress. I just didn't know if any of the other ingredients would hurt it.