The last few years, I have been starting my seeds & water them when I thought they needed water. This year I got a bright idea. I got out my extra food scale (it's not digital) & put it on a tv tray next to my grow lights. The seedling that I have not transplanted into pots, I'm weighing them to see how much water is in each Rubbermaid trays. No more guessing, under watering or over watering. I just wish I thought of it sooner.

I have a suspended water jug (about 4 gallons) on a platform in the basement rafters. A tube is run through a rubber cork & it uses gravity to let the water flow out. It has a pinch clip to close off the water flow at the end. It is slow to water the plants but never hurt the seedlings. I had to find a chair to sit as I water.

Any of you have a watering system for your plants under lights?