I have the black hanna combo PH/EC/TDS meter model HI98129 the link can be found below. I ordered ph calibration solution for the meter both 4.01 and 7.01 as the instructions indicated but my supplier sent me 7.0 instead of 7.01. Question: Can I calibrate my meter with the 7.0 or is this not recommended? I await your responses. Thanks GC! http://www.sunstoneherbals.com/hanna_combo_ph_ec_tds_temp_waterproof_tester_hi98129.htm
Did he send you a Hanna product? Either way i have found any fresh pH cal solution works if the probe is cleaned well with softscrub and rinsed well in water. Make sure the end of the probe stays wet at ALL times when not in use and for 24hrs prior to calibration for the first time.
I have that meter and I use the GH 7.0. When i bought the meter the hydro store also sold me the cal solution. I'm on my 2nd grow using it and no problems. like oci said keep the probe wet with the solution. I have to put a few drops in the cap about once a week.
Been using tap for storage solution from day one on my $300 BL meter and others with great results,same probes too.
I cut a little piece of sponge to fit in the cap to keep the tip hydrated. It holds the solution without spilling or over filling the cap. Tile grout sponges work good because they are more dense than kitchen sponges.
Great idea chunk!! All my meters use BNC connectors so they have rubber boots which hold water for months if needed,seen some probes that have sponge material in the caps factory.
Haven't had to use the ole meter much since I hopped on the organic bandwagon, but I do test my runoff once in a while just to make sure my soil is buffering my water. My well water is 7.4 pH, runoff is 6.3-6.4pH.
