fishboy, that was flippin hilllllllaarious
If i might add to the other well-thought-out ploys, I would say that after you get that initial fish tank (you know you will

), if you want to get more, or bigger, fish tanks this is a guaranteed method right here. It sounds corny at first but stick with me.
Do many many fish related things in front of her.
examples:
*go to fish stores often and spend lots of time there just "browsing"
*visit fish websites for long durations of time then afterwords share with her what you have learned
*make "fish friends" and talk to each other constantly, whether at the bar or on the phone, in "fish code"
*finally, and this is the eaaasiiiiest one, stare off into space with the "Im deep in thought" look. When she asks what you are thinking about, shrug your shoulders and say "Oh, just looking for flaws in my potentially new livestock plan"
After a month or two of this you will be officially branded a FISH DORK. And heres the trick. Women love dorks. I dont know why, they just do. So they will back you up on your little "fish fetish" as long as it doesnt injure the bank
too badly and you let her joke about you (in a loving way) to her friends.
Thats it. Thats the secret.^^