Dechlorinator expiration date

[whizzvet]

Hi there!

Only after putting the dechlorinator in my (still empty...) fish tank have I noticed that is 1 1/2 years past expiration date (bottle says October 2007...).
The instructions in the box say to not use after expiration date... Is it dangerous for the fish I was intending to put in the aquarium next week? Or is it only uneffective? Shall I remove all the water, buy a new dechlorinator and refill the tank?

T(h)anks for all the help!

[CaptainAhab]

I'd think just possibly ineffective but call the manufacturer just in case.