Does copper power expire?

[lagatbezan]

i got a bottle of copper power in my fish room that's about 8 years old. Does it go bad or lose its concentration? Should I keep it or throw it out? There is no expiration date on it anywhere. Any suggestions?

 

[HotRocks]

i got a bottle of copper power in my fish room that's about 8 years old. Does it go bad or lose its concentration? Should I keep it or throw it out? There is no expiration date on it anywhere. Any suggestions?

My recently purchased bottles have expiration date of May 2025. So that's over seven years from purchase. Who knows how long they sat before that...

I don't know enough about chemistry to know if it can degrade over a longer period of time than seven years or not. Maybe @Christoph or @Randy Holmes-Farley can help.

 

[LittleMaui]

Anyone able to answer this question?

 

[TheGreatWave]

I read on the internet a long time. lol!

I'd say if it's Sunday night and the LFS is closed I would go ahead and try it. Give it a good shake and look for stuff in the bottom of the bottle.