I just moved a 1.5 inch bluegill into my 10 gallon tank, because he was being bullied in his 20 gallon. The 10 gallon ha 3 zebra danios in it. When I put him in, they all started swimming around, right under the surface. What are they doing? Are they Ok?
your tank is way to small for a bluegill. Bluegill also need to be kept in groups, and he is probably scaring the danios because he will eventually eat them.
ADD: A twenty gallon tank is too small for bluegill, too. If you consider the fact that they need several blue gill in a school to keep them from becoming stressed, and he will get MUCH bigger, most people do not advise anyone to keep bluegill in anything less than 100 gallons.
