do you think this meter is good and will be the only meter i will need to start with? also does this meters probe need to be constantly wet like my ph pen? do i just leave the probe in my res with this one? thanks guys! sorry for this dumb question.

Milwaukee SM802 SMART pH/EC/TDS Combined Meter/Tester - eBay (item 370181371170 end time Apr-29-09 12:36:50 PDT)