Well, don't just sit there, go to city hall and speak your mind. Ask them if they plan on limiting the number of fish a person can keep in an aquarium too. How are they going to enforce this? What other types of animal ordinances do they have? Recently in St. Paul they passed an ordinance against keeping sugar gliders. There was a notice posted in the paper about the impending city council vote and there was plenty of time to send in comments. You know why the ordinance passed? Because NOT ONE SINGLE PERSON showed up to speak against it. A lot of these laws get passed simply because there is nobody voicing an objection.
Mark