Hi,

The Hanna HI98130 is a very nice combo meter.

I'm sure you tried using the HI7030 calibration solution and checked your batteries or perhaps it is time to replace the pH probe.

http://www.caprockdev.com/PDF/98129_30.pdf

It's not you it's the meter. I'm very familiar with this meter. A few things can be happening. One, the probe is shot. They are replacable for about $60.00. Second, the internal processor could be confused. Do you have it set on the proper calibration sol. 7.0 in the mode settings. Thirdly, the worst one it could be dead. Lets put this way, I work with ph and EC meters every day, and 1 out of 5 of this exact model wouldn't even out of the packaging. Hanna needs to stop making them in third world countries. I do not recommend this meter to anyone.

I just thought of something. When you go to calibrate it and it ask for the ph 7.0 put it into the pH 4.0. Sounds wierd, but I have gotten this to work. I quess it reconfuses it or something.

Suggestion: Look into the Blue Lab meters. They are out of New Zealand and are distributed in the us. Very solid equipment, and you do not have to calibrate the ppm/ec on this unit. Pretty cool.

Good luck

Artisan and oakton both make good meters that are cheaper than blue lab with the same quality (accually better). hanna is junk there is no quality control at there factories

Is it OK to purchase a combo meter like this? I read somewhere that it's not advised.

I guess I need to get one. :(