I feed once a day in the morning right after lights on for the plants i hand water. My bigger/keeper area i use blumats, so they are getting steady feedings....better yields vs hand watering.......but they can be a pain in the ass! You might need to do twice a day in 2 gal depending on plant size. Usually if the top of the coco is dry, they are thirsty.....only feed enough to get some runoff. A good way to tell is to lift the corner of the container....if it's light, they are thirsty. IMHO they key with coco is to keep it moist so your nutrients don't crystalize, but you don't want it saturated. You definitely don't want it to dry out though, that will lead to issues. I use GH Cocotek, doubt that makes a difference. Watering once a day in 3 gal bags, i can get 6-8 zips per plant, sometimes more. With blumats, i can get 8-12, same set up, just steady watering from the blumats. Plenty of people getting 10+ in 2 gal bags watering multiple times per day with pumps and manifolds, or even hand watering if you don't have a day job. Just keep em moist, and you'll be good...you can then tweak your method and schedule off that to suit your lifestyle. All depends on how much work you want to put into it. I use jacks also with calnit, epsom, and silica. I tried using floralicous as a booster, and it did the opposite.
too much gorilla glue this evening lol