Instant ocean salt mix and salifert test kits

[reefnut]

how old is too old.I have a bucket and a half of the salt mix that is approximatly 2 years old.Just set my nano back up and hope its still usable.what do you thing its been sealed and is not contaminated in any way.does the salt expire?as well i have all my salifert test kits with at least half left in each.NO2,CA,NH4,NO3,PH and KH/ALK. is this the makings for my new tank or am i going to have to get new ones.again nothing is contaminated in any way.thanks in advance.