Fresh to saltwater ??
 

Hello, i currently have a 75g tank set up and fully cycled for fresh water. I was waiting on a Jaguar cichlid to come into the lfs, but the other day they got in a spiny box puffer or striped burrfish whichever you like to call it

My question is will the tank need to be recycled or would it be safe to add salt, wait a week or so and put the puffer in? Or are the bacteria different in salt and freshwater?

Thanks for the help

If it was me I would start all over.
Saltwater aquariums require different substrate then that found it a freshwater tank. I would then add fresh water and add salt and live rock to the tank and let it sit for a couple months to insure it was cycled before adding anything.

Just my 2 cents

You can't just throw a SW fish into SW and expect it to live, but I'm sure you suspect that. :)

I would suggest this site as a good info starter.....

http://saltaquarium.about.com/mbody.htm

The bacteria is different and a total recycle is required.