I have an African knife (those long, wierd shaped fish) A lot of times it trys to jump out of the tank(thats what it looks like)!Is this normal or does it think it sees food or somthing else. Plus I never actually seen it eat I feed it what I feed my other fish. Please if anybody knows tell me, Its very hard cleaning out the tank thinking that fish could jump out, it scares the h*l out of me. 
