great simple sticky here!

Correct me if I'm wrong.... As I understand, when using RO or distilled water, we need to use an additive like CalMag Plus because most hydroponic nutrients are not formulated/balanced for use with the plain water. The nutrients are made to be used with average hard water which already contains calcium and magnesium. RO/distilled water lacks the calcium and magnesium which are essential for growing.

However, using hard water from the tap isn't always the best because the ratio of calcium to magnesium can vary, possibly to the degree of causing nutrient lockout.

Some people use a mix of plain and tap water. I don't know enough about that to make any comments.

I'd think it would be more beneficial to use RO/distilled water and adding the appropriate amount of CalMag to correct and prevent deficiency, which will give the plants all they need in a soluble form they can uptake with less effort.... Also there's no harmful mystery chemicals as would come from using tap water!
GreenDestiny Reviewed by GreenDestiny on . If you use RO or distilled water you NEED CalMag Plus That's all. My fingers were cramping from typing it n times a day. Rating: 5