Thai Oranda Rosetail Calico Gold

Goldfish can be found in slow-moving, freshwater bodies of water. As with their close relative the carp, they thrive in slightely sludgy water. In an aquarium, bi-weekly water changes are a good idea as a goldfish tank is hard to keep clean. They thrive in a pond environment thus the addition of real plants is optimal if the owner is prepared to replace them fairly regularly; goldfish enjoy eating live plants. An aquarium with a dirt bottom is ideal but difficult to maintain. Small pebbles are a suitable substitute for the pond-like bottom. Typically, goldfish will survive in water temperatures ranging from freezing to 30 degrees centegrade. Fancy varieties(orandas, lionheads, ranchu, veiltailes…) should be kept in water no cooler than room temperature.

As there are over a hundred varieties of goldfish, coloration and physical characteristics vary greatly. The common goldfish has two sets of paired fins – the pectoral fins and pelvic fins, and three single fins- the dorsal, caudal, and anal fin. They lack barbels on the upper jaw, and lack scales on the head. Goldfish have exceptionally large eyes and acute senses of smell and hearing. They have 27-31 scales along their lateral lines. Goldfish have (rather than true teeth ) pharyngeal teeth in their throats which they use to crush food.

Goldfish can grow to be 3 kg and 45 cm long but are usually much smaller than this.