The two basic types of goldfish are scaleless and scaled. The scaled varieties include the common goldfish, fantails and comets. These fish are born a silvery olive-grey and will remain so for 3-6 months, and then develop their scaled color. The fish that do not color up usually become bait fish.
The scaleless fish are actually not scaleless, they just have transparent scales that appear more like skin. This creates a glowing feature, as demonstrated by certain forms of Shubunkins and Calicos. These fish appear white at first, but eventually develop colors much like the scaled fish do. These fish are just like fingerprints, no two are exactly alike.
Age, Breeding, and Hatching
Trying to determine the age of a fish is difficult, especially as fish grow at different rates. A rough rule can be applied: if a fish is 1-2 inches it is around six months old, while a fish that is 3-4 inches is about two years old. Growth will slow after this point, and becomes dependent on their surroundings. Fish that are outside generally grow quicker than indoor fish. In order to determine the age of the fish, a microscope must be used to count the rings on the scales.
The average gardener does not need to make special accommodations for breeding, but it is important to know some fundamentals. Healthy goldfish will breed from about one year on, and outdoor fish will breed in the spring and early summer. The female, swollen with her eggs, will brush up against plants to deposit the eggs. The male, distinguished by white spits near the gills during the breeding season, will follow around the female fertilizing the eggs. Most eggs will be eaten by baby fish that hatch, but those that drop into secluded places will hatch and be left alone by fish.
To make sure the eggs hatch, you will need to remove the plants with eggs, and place them in 70 degree water, the fish will hatch in roughly 5-6 days.
Powdery rice flour will make a great food source for babies. Sprinkle it lightly on the top of the water for the first few days. The very first few days you will want to feed your fish hard cooked egg yolk forced through a cheese cloth. Add snails to the water, these will eat the excess food.
To raise the best goldfish, you will want to eliminate the weakest and smallest. By the middle of summer, you should have twenty or so of the strongest fish left which can be moved to the pool by late summer. The older fish should leave them alone, as long as they are large enough in size to care for them.