JAWS
Is that stuff all digital?
The PH pen is I beleive. Check out the site:
http://aquariacanada.com/osCommerce/...db66400e0b2953
REEF_RAF
Plastic swing arm calibrated against a refractometer - about $12
I had the plastic swing arm checked against a glass hydrometer when I bought it some 10 years ago(refractometers were not available then
). I guess over time something happened to the swing arm.
Dave