Quote Originally Posted by Aaron385
As far as doing hydro without an EC or PPM meter.. the best I can say is one day your luck will run out..
I said I did this for a couple years with great results. I don't anymore, since meters are so cheap now. It's not hard to get away with. You just start with 1/4 strength of what the directions call for, then gradually increase until you see small signs of over-nuting, then back off a little, and the proper ppm level for your particular situation is established.

Or buy a meter for $25.