depends what kind of fish you mixing like if it is 2 Siamese boxing fish they will kill each other if it is a women of the species as the fish more likely yes
Your goldfish will not live "longer" no matter how many or how few you have.
Yes,fish make u live longer. it also increase your mind power.
The fish and/or other creatures can no longer live in the habitat for that habitat is to cold.
In general smaller fish have a shorter lifespan.
it live like any other fish
I don't think so. The fish Kind have all different life times. So do dogs, But i think dogs live longer from past experience.
yes they can live with other fish because there not prone to dissease
koa fish can live with minnows
Most female fish live longer than males, eels are no exception.
Cleaner fish live in coralreefs where they can easily find other fish to clean.
Hag fish
Other than some fish and clams, tortoises and sea turtles are the higher lifeforms that live the longest, up to 200 years or possibly longer.