[macojoe]

first whats wrong with the tank?? When i bought my boat they told me the tank did not work and it was just the vent, I know of another that was the same.
If it is leaking have a pressure test done to see if it really is? Might just be bad hose or something?

After you have found out what is wrong if anything then you can decide what to do.

I would never add a open tank in the cuddy area for safety reasons!!

You could pull the old tank and add a cheap plastic tank till you have the cash for a new one, or you can do like reel and add them under the seats? But there is a better option then in the cabin!