Fish behaving erratically

One of my fish for no apparent reason just took off around the tank, banged into the sides and nearly jumped out, stress bars out and gills flaring, seemed distressed then few mins later was fine! Any ideas what caused it, everything else in the tank peaceful thanks for any help

Hello! And welcome to SimplyDiscus! Sorry you are having issues with your fish. To help you we need more information though.

Can you fill out this questionaire...

http://forum.simplydiscus.com/showth...lease-complete

Cut and paste to this thread..Thanks.

Al