If a ‘king of the aquarium’ is mentioned these days, it’s usually in a discussion about discus. However, the regal post was held not so long ago by another fish, also very beautiful, and easily accessible to just about every aquarist – a fish that nowadays we see so often that their beauty has become commonplace. This fish is, of course, the guppy, Poecilia reticulata.   By 1960 the many forms of the guppy we know now were well-established – veiltails, cofertails, flagtails, swordtails, lyretails, pintails, speartails – and in Aquarist and Pondkeeper editions (now Today’s Fishkeeper) from the 1960’s nearly every issue included something about the guppy. In an open show one (non-guppy fan) person was upset that there were as many classes for guppies as for the rest of the species combined – a view not held by others on the letters page who couldn’t get enough guppy stories and activities.