I need a good digital ph/ec/ppm tester

i got a hanna ph tester on ebay but it ended up only showing temps in celcius so i returned it.

i am doing hydro. i would like to keep track of my water more accurately than with the little chemical test kit.

can anyone recommend a good quality, low cost tester that i can get accurate results with?

good quality AND low cost? thats kind of an oxymoron. you get what you pay for. personally I use a hannah and love it, its very easy to convert c to f and vice versa but I guess to each his own. have you looked at milwaukee testers? Milwaukee Instruments

i followed the instructions on my hanna to convert from c to f and it wouldn't do it after many repeated attempts. even others tried and it simply would not switch.

how would i go about accurately calibrating it to assure proper ph adjustment???