dead fish don't always float to the surface.
yes, fish hide. There is plenty to eat on the bottom.
If the others aren't spooked then its less likely that you have a predator
ronm

Yup, and sometimes sick fish will sulk at the bottom/hide for a long time
before they die.... and sometimes they'll snap out of it, and you'll see
them again weeks later. ~ jan

~Power to the Porg, Flow On!~