i dont think i have any fish that have weid habits
but i do care for a SW stingray at where i work for volunteer time
this ray is huge about 30 inches in diameter and during feedin time he will swim up the wall of the tan kand do a half barrel role so then hes upside down and hell swim on the side of the tank where the food is, he actually wants the person feeding to drop a squid right in his kisser if it dosent make it to his mouth he'll make a "cup" and draw the squid toward his mouth.
he have another ray in the petting pool, we call him porky (for obvious reasons),
and during feeding time he will jump half way out of the water sticknig to the tank and make these sucknig noises and flap his disk asgressively and get everyone wet. Hes basically saying GIVE ME FOOD NOW!!!!, but we cant give him food because hes half way out of the water so we have to gently force him back down and give him a handful of krill
hes my favorite fish at that place
i sohuld get pics of these rays
saturday

need soem batteries though, lol.
i wonder if FW rays are the same way??