I would like to know how to contact Salifert. I have two Salifert test kits CA /MG with 2015 / 2016 expiration dates on the boxes. When I compare the club Reference 520 / 1300, my readings are +100 / 620 on the Ca; and -100 / 1200 on the MG. When I test my water in the barrel, I get 520 & 1290 readings but my salt box says CA ranges between 390-410 and MG 1110-1250. How can I tell if my reference is out of date or incorrect, and how can I get Salifert to send me new test kits?