Hi everyone! I'm upgrading my tank from a 40g fwlr to a 65g, so i need some advice!

I'm gonna use my fluval filter until the money builds up to buy a new one. But I need to know what kind of media i should use in it? Should i use carbon or not? Any advice is usefull to me, so throw your comments at me!!!!

Also I have alot of sea shells that I brought from europe (The honeymoon). I would like to use them in my tank. How do I get them ready or treated? Also are they any good broken up and used as a base?

Ok....I think thats all the questions I have. So please feel free to e-mail or post any suggestions.

Thanks.....
WildCat