How long can a hydro system be left unchecked?

Im growing organicly right now but have been seriously thinking of switching to hydro...the problem is that I might have to be gone for periodes of 1, 2 or even 3 days due to my job...

I know id be taking a chance by leaving any hydroponic system unchecked for even 24 hours... but lets not take luck into considaration...is there a system that could continiously suplly nuts and water for a periode of a couple of days?

of course there is.. your only problem would be the rising of your PH. i've left for 3 days with no trouble but i'd say four is pushing it

my record is 13 days without touching a thing.

* I was going on vacation and bought a large res which gravity fed my aeroponic/DWRC system with a float valve. When I got back I estimate I still had 1 or 2 days worth of water in the res and maybe another 2 days in the system itsself.

my record is six hours i wont leave her alone for nothing im chained to it my girl sead im cheating on her with my aroe, im obsesed like lord of the rings PRESSIOUS. lolz no realy a pump can go out n it has if i dont check i could be in big trouble well not realy but shure would suck to find your shit wilted n in no shape to recover.. FUCK THAT IM A SMOKKKKKKKERRRRR.....