The pic with the damaged/deformed leaves is not bug damage but root stress most likely caused by the pH being out of range when the leaf was forming. Initial signs are leaf twisting/deforming that will eventually start showing weird splotching marks. When just the edge of a leaf curls up a little, that’s from humidity being a bit too low for the temp.

The more you spray and wet the plant, the longer it will take to acclimate to lower humidity out of the dome. I never spray clones in a dome anymore.

No such thing as too much water. Only not enough oxygen. The lack of oxygen that suffocates roots has nothing to do with any form of hydrogen.

They will not consume much water or minerals when they’re small. Their consumption will increase as they grow bigger.

It’s ok to use but I wouldn’t spend money on it. Deuterium is 1 of 2 stable forms of hydrogen. It’s not very abundant in water so it’s not something I’d be concerned about removing.