My Fish Tank Blog

Since I started keeping tropical fish, I have become aware of the colour coding system used by retailers to alert customers to the temperament and compatibility of their fish.  Often, red is used to denote aggressive fish; yellow for semi-agressive; and green for passive or peaceful fish.  I think this forms a good basic guideline for potential customers.  But, I would avoid relying solely on colour codes and buying on their recommendations alone.  For example, I have seen keyhole cichlids which have been given the same red classification as convicts.  In addition, the colour coding can be over-simplistic, not informing us about water, diet, tank size, etc.   The colour coding, however, is a good starting point for selecting suitable fish.  Also, it can be useful to talk to fish shop staff about compatibility, etc.  And, of course, there are many informative factsheets about tropical fish species on the internet.