I'm kinda in the same boat with DrFelterpus, I was gonna but some sunshine this weekend. I've only used typical soil. And since peat moss is a soli-less mixure, I'm sure sure whether you would need the higher pH like with soil, or the lower 5.8 like typical hydroponics.
I've never actually checked my run off, I just check the pH of the soil from time to time. Though the testers i can find for soil, aren't very accurate, unlike my combo from Hanna. however it was only a fraction of the price compared to the Hanna. My pH stay pretty much about 6.5, atleast thats where the needle lands.
AS for your water question, if you have to feed you plants water each day, because it gets used up or whatever, then yes, you'll want to use plan water every other time you feed. I'm able to get away using nutes evertime i feed, because my feeding are about 3 days apart. If I had to feed every day, to make sure they don't get under watered, then I would use plan water ever other time. My soil pH tester i mentioned earlier... it also doubles for a moisture detector. you just sick it int he soil and it takes the guess would out of when you need to water. they are about $12 at lowes or home depot or any garden store.
And if you want to increase root growth use voodoo juice if you can afford it, but really any beneficial microbial works. sensizym, Piranha and tarantula all work to improve root growth.
I did find this about Mix#4, There was a question whether or not it had nutes in it already. this was one of their bullet points.
No-Burning: inert formula accommodates custom feeding
practices with no conflicting nutrients or burn risk.
So I assume we're good.