Testing kits

[the caretaker]

I have just sorted out under my tank and for one moment I thought I'd found lord Lucan LOL, but what I did find was an unopened but 5 year old tetra nitrate testing kit, could it have gone bad by now? should I throw it away?

 

[WILDER]

No, if it's not been opened it might be ok, but no expert on these things.