Hanna meter gone wacky

I have the meter pictured in this link ( http://www.htgsupply.com/viewproduct.asp?productID=53779 ) for my E&F garden. I bought the meter as a continious read meter to place in my reservoir and leave. HOWEVER....when I place the probes in the reservoir, the pH reads 0.00. The TDS and EC read properly, as does the temp,but pH flashes 0.00. If I take a sample of the res in a seperate container, I can test the pH of it just fine,and it is usually 5.8. Then, put the probes in the res,and pH 0.00. Any idea why this is happening?? Thanks for the quick reply and any help.
ppm

send back 2 company for new one. Buy a Milwaukee next time.

Is it calibrated?
Is it touching anything?
Is it hanging in a way that it could be stressing the connection?

shouldn't they be built to withstand a "stressful connection". Calibration is good. Im sure this meter came with a few pouches of calibration fluid.