feed-water-feed isn't really necessary... I think you can fert pretty intensively if you get in the habit of flushing... I've never used one of those flush solutions unless you count cannazyme, but that's more for dealing with dead root mass etc. I like coco because it's SO easy to flush.
Thanks for the wishes, I'm looking forward to seeing your balcony grow (possibly in person!!!) when it warms up!