tongascience
New member
marinedepot.com refractometer item #md2101 / is very inaccurate! after calibrating at 20'c/68'f .& after 30 sec reading 0 ppt .it tested 40 ppt on a reef tank.when tested with another calibrated device =35 ppt ? anyone else have one of these - high quality extremely accurate marinedepot refractometer ?
