the time that you wait to harvest is worth much more than a seed, i'd use good genetics anyway. a plant's requirements differ a lot with climate. i would estimate like 1/2 L to 1 L per plant per day in summer, but thats a wild guess, plant size and medium as well determine water requirements. i don't know about these self watering systems, but there must be several ways that it can be done, however, I think that you are adding risk by placing a system there, if cops see it, they are more curious to know who made it imo and they have a nicer tighter case that they can frame a grower with. i don't mean to scare you, i'm only saying, it's way harder to have you busted with no system whatsoever. they would have to see you watering the plants and still you would have some degree of deniability, whereas if you have a system, they have evidence, probably can get a fingerprint too, and as soon as they see you in the area, they have something to connect you to the plants. actually i find it safer to grow at my own house, no matter what. I don't know about others, but where I am, it is very unlikely for a neighbor to call you in on a mj grow even if you were foolish enough to have them discover it.