Should you bury a fish

You can if you want. However, the proper thing is flush him/her down the toilet, because that's what everyone does! :)

ANS #2

Burial is for the benefit of the survivors. If it helps to overcome the loss, the fish ought to be buried. It is just as appropriate to convince the bereaved that burial at sea is a fitting interment. If you are convincing, you can bury the fish with a flush.