As for testers I use the Hanna 4 in 1 model. It cost a little more then some of the others but worth every penny. You need the full range of calibration solutions and if anyone tells you different (they are wrong) This is a scientific internment and should be treated like one. I calibrate mine once a month at least and it has lasted me for 3 years with no problems. There are others cheaper but you get what you pay for.
Zandor Reviewed by Zandor on . First Grow Hey, I've been soaking up information to start my own grow. I kinda got ahead of myself and just jumped into it. I started with 4 plants but only one has sprouted from the RW. I think that has to do with how they were put in the rw. I've got a 4'x4'x8' room painted flat white I made a DWC setup out of some tote things and some net pots I only have a bath exhaust fan in my room for ventalation My light is a 250w HPS that I got from gutting a street light Dyna-Gro Neuts I have one of Rating: 5