Nute feeding Question

Do I have to add nutes every time the water in my AG gets low?

Pretty sure most people add nutes every other feeding.

I did every other...in between I just added ph'd water.

Junnk: I think we may all be doing it a little differently. I have weekly 'leftovers' when I mix and change my gallon of nutes and I add it during the week in between refills with pH balanced water like LorDeMo and K21701. I don't have a ppm tester so it's a shot gun way of keeping my nutrients replenished and my plants seem to like it. If you change your nutes weekly you'll find that growing our favorite herb can be very forgiving.