Hi! I don't really know if this counts as cleaning equipment, but I was wondering if there was an expiration date for seachem prime. I bought some a while ago thinking that my old water conditioner was about to run out, but it lasted longer than I thought, so the prime kind of just sat there, I think I used it once when I first got it. That was a couple of months ago, and when I finally opened it again today to use it, it smelled really bad, like something rotten was in there or someone farted or something. I know that's a weird description sorry. Did it go off? Should I not use it?