People keep fish as pets. We name them. We notice their personalities. My Jiggles was always the first to go for the food and Hit would just follow her around and contentedly pick at the rest, but they were both goldfish of the same breed from the same shop (maybe even the same parent..)
My point: Apart from the horrors the fishing industry wreaks upon our environment, upon small and large scale ecology, and upon larger and more obviously 'worthwhile to save' animals like dolphins, sharps, porpoises, turtles, etc... And apart from the fact fish, as any animal, is a biomagnifier of toxins and pollutants.* I think the fact we grow so attatched to pet fish should in itself make it pretty darn clear to us that they are
As for lean protein.
Fish as a Lean Protein:
Protein:Fat is 1.867
Tofu as a Lean Protein:
Protein:Fat is 1.857
Notice--fat to protein ratio pretty similar... Tofu is far from the only substitute that will win this little battle, but its also the easiest to find commonly in restaurants, fast food joints, cookbooks and the supermarket.
Now that we're comparing protein to tofu, lets notice fiber to protein.. tofu has SIGNIFICANTLY more dietary fiber per g protein (over 3 times more). Tofu has no cholesterol, an abundance of calcium and comparable iron. True it's lacking in vitamin A and C, but as a vegetarian I'm assuming you will eat a vegetable at one point in the day and be fine.
*This is a natural occurance that only gets worse the higher up on the foodchain you eat and IS significant. There is a reason why birds die off when DDT is used to spray crops, which the bugs eat and biomagnify), which birds eat and further biomagnify, which raptors eat and die and/or cannot reproduce.
Hope this helps you. Dietary choices, as everyone here knows, is a big choice to make whether its for health, ethical, or even practical reasons. I think I speak on behalf of the vegetarians here when I say we would love to see you become vegetarian and refrain from eating the flesh of our Pisces friends. Welcome to the VB