dfollet,
If you use 3 cups synthetic fertilizer with a relatively high NPK (like Osmocote) in the EarthTainer fertilizer strip, then additional feeding during the Season should not be necessary.
If however, you use a low NPK Organic fert like Tomato-tone / Plant-tone then I would recommend supplemental feeding during the year. Cukes especially need this additional feeding in my experience.
I can also use the EZ Flo to inject Azos, Great White and other water soluble nutrients like Calcinit easily. Wish I had installed this 5 years ago.....
I give the AWS system 1 hour per day access to the feed-water, not that it is necessarily running for that entire duration. Typically each EarthTainer in the system shuts off its individual AWS intake valve after about 40 minutes. More during the hot weather, so I give them 60 minutes access time for a safety margin.
Raybo