Litermeter 3

[Jack]

Kent float valve:
http://www.jlaquatics.com/cgi-bin/sh...no=ro-kpfvalve

Auto-shut off:
http://www.jlaquatics.com/cgi-bin/sh...gno=ro-kpfvkit
(I just read closely and it says "Not recommended for level control in aquariums." But I know people who do this, but if the product says not to I wouldn't reccomend it.)

So, float valve is my choice. You have to have it gravity fed and a resivoir installed though. Depends what you're going for.