I'm a novice grower having the same questions...
I'm growing in ProMix in about 4gal pots that holds moisture great. I only really need to water weekly, but feel like I should be watering more. The plants don't need it so I don't, but I feel neglectful anyway. With nutes, I'm even more confused. I've been feeding weekly, and may switch to every other week. I have a Super Lemon Haze, a Thai Super Skunk, and an LSD. The SLH and LSD I grew from seed, the TSS was a clone from a friend. I've burned my LSD, and TSS by overfertalizing, requiring flushing with successful recoveries (albiet slow growth bursts and a few lost leaves), but my SLH took the same nutes fine. I plan on growing single plants of many strains, but seeing the way different strains use nutes differently, I may reconsider.
I think I'm going to switch to nutes every other week, and plain water with maybe some mild sugar and B1 in between.