how long will substrate last in it's sealed bag? i got it shipped to me from petco.com but i dont think i will add it until like 4 months from now until my betta fry are full grown. is it alright if i just keep it in the bag in my room until then? it's in a sealed bag i didn't open it. it did have water in with it though because it's substrate. would i be better off selling it on aquabid.com and getting it when i want to use it?