Fly Fishing Ornaments

Question on cleaning my aquarium?
I have two ornamental fish of 6 years, which are about 10 inches long. Recently crazy when I try to empty the tank. They fly around the tank and run into the wall at the point where the mouth begins to bleed. I wonder what I'm trying to make a network, or what I do. My tank is a 150 gallon
Such behavior may indicate poor water conditions. Check parameters of water in search of high concentrations of nitrates or ammonia. If this is the problem to begin making water changes every day until small, the problem disappears. Do not make a big change 20% per day is well and safe. Fish netting increase the problem.
