On Thu, 17 Aug 2000 21:19:53 -0400, Kevin Zippel wrote: > Liquid calibration fluids have a shelflife of 6-12 months, tops. > Refrigeration helps. > - - - snip - - - > ATC (automatic temperature compensation) is worthless. Kevin and Everyone - Does temperature become an issue if the meter is calibrated in solutions that are a little/a lot cooler than the aquarium? David AGA, Paris