For its size, the crucian carp remains a very hardy fish which can stand water conditions that would kill other species.  They are also reputed to be capable of surviving being buried in the mud of a dried up ponds during the summer.

Spawning begins when the water reaches 14-15c with a group of males pursuing a single female in weedy shallow water.  Each female will lay about 250,000 eggs which are fertilised by the males.  Eggs hatch in two to three days with the larval carp feeding on the yolk sacks.  The fry feed on plankton and algae before turning to larger food as they grow.

Unlike other species the crucian carp do not lay their eggs in batches so run the risk of having their eggs left high and dry in times of sudden drought.  For this reason whole year classes of crucians can be missing at some venues.

Although the crucian carp is not held in the same esteem as its larger carp cousins the crucian remains high on the target list for true specimen anglers.

The variation in shape of a Crucian carp can be very high. The fish get an almost perfect disc shape with well rounded fins. If no predators like pike or perch are present, the Crucian carp will grow in length rather than height and the fish will be more slender looking. The growth in height will make it difficult for predators to swallow the crucian carp.