Enough with that!.....lol...I use hydroton in 8" net pots...my pump runs 15 min. at a time, 6 x a day....I've been doing this for 2 years with no problems....just try not to feed with the lights off.
when i ran my ebb n flow i ran pots with hydroton...i flooded my tables, every 3 hours, for 15 minutes only during lights on....no flooding during lights out....
I would do 3 times a day for an hour at a time. It all comes down to you what you think is best I'm using coco chips with air pots, I chose coco chips because it doesnt retain as much water as coco coir and I can flood it like I would hydroton, but I recently changed it up and made it a top feed system watering the ladies 3 times a day for 1 hour at a time.