I'd recommend the Tropf BLumat autowaterers, as each plant would get/use exactly as much water as it needs, with no pumps or timers, just gravity fed. Check this site out for more info:http://www.blumat.at/automatic-watering-system.php#bltropf
I just set up 60 of them in my veg room (indoors) and have another 100 for flower. After 3 days of use I'm hooked, regardless of the plant size every one has a perfect amount of moisture. My reservoirs top themselves off daily, and each string of plants has it's own manifold (3/4" poly hose) with blumats plugged into it. Very simple, but at $5/valve not exactly cheap. You can feed through the line as well, I do recommend salt-based nutes instead of organics to avoid clogging the little 3mmOD line.
I just set up 60 of them in my veg room (indoors) and have another 100 for flower. After 3 days of use I'm hooked, regardless of the plant size every one has a perfect amount of moisture. My reservoirs top themselves off daily, and each string of plants has it's own manifold (3/4" poly hose) with blumats plugged into it. Very simple, but at $5/valve not exactly cheap. You can feed through the line as well, I do recommend salt-based nutes instead of organics to avoid clogging the little 3mmOD line.