Would you like to give them a call and ask if that means the lot numbers were made in 1999?
Also, maybe ask them when was the actual "expiry" date to confirm long over they are? You could also check again about the Saltwater testers being used in FW and see if you can get a firm answer if they are okay.
8:00 AM - 5:00 PM Eastern Time (Monday through Friday)
(800) 847-0659
http://aquariumpharm.com/help-desk/general-help.aspx
Only an idea if you have time/feel like doing it of course.
t
* edited to add info
