Just to make a comment here, on the rez thing.
The bottle says don't premix cuz ferts tend to bind together when mixed straight, without water. The company wants you to avoid losing fert strength through the mixing of ferts together, so they say don't premix meaning don't mix ferts without water. The method of dipping a bucket into the rez water is good cuz you're mixing your ferts into water, them dumping them into the rez, which is more water. All you have to do is mix any ferts into a common container that has water in it to avoid binding of nutes. It's the same with other chemistry.