Creating the perfect home for your goldfish
The history of the goldfish is almost 2,000 years old. It began in ancient China, where goldfish (Carassius auratus) were caught and transferred to backyard ponds to ensure a constant supply of fresh fish. Among the silver-gray individuals, there were occasionally fish with orange coloration. It is believed that these fish gave rise to the goldfish breeding that continues to this day. Hundreds of years of painstaking and patient breeding work have led to the creation of individuals with bizarre shapes and diverse coloration. Today there are about 300 varieties of these unusual fish! If you are planning to get a goldfish, it’s essential to learn how to prepare an aquarium with the right living conditions.
Varieties of goldfish
In terms of body shape, two groups of goldfish can be distinguished. The first includes fish with an elongated body and a single tail fin. It is the oldest variety bred in China. While its body shape corresponds to wild carp, the distinguisher is the coloration. Goldfish can be yellow, orange, red, gold or red and white. Calico forms are called schubunkin – their bodies are covered with a multitude of red, yellow, orange and black spots. This group of fish is kept primarily in garden ponds.
The second group consists of fish with shortened thorax and double fins – caudal and anal. They include many breeds: veil, fantail, ryukin, oranda, oranda red cap, telescope, demekin, pearlfish, varieties lacking a dorsal fin – ranchu, lion head, bubble eye goldfish, celestial eye goldfish, nankin. Goldfish in pet stores meet the breed criteria only to a small extent. If you want to buy a pedigree fish, look for goldfish importers, specialized outlets or buy directly from breeders.
How to set up an aquarium for goldfish?
The minimum aquarium capacity for two goldfish is 120 liters and with 50 liters for each additional fish. Goldfish feel better in a group, in which they are more active and “cheerful”. It is best to keep them in a 240-liter tank. Not only because you can nurture up to 5 fish in it, but also because it will be easier for you to maintain good water parameters in the tank.
Goldfish are very dirty fish. They have a rapid metabolism and they are constantly digging up the substrate, which makes the organic matter accumulated in the substrate go into the water column. For this reason, their aquarium should be equipped with a large bucket filter, intended for a larger tank. It will ensure more filter bed, on which nitrifying bacteria will settle. It’s also a good idea to use a second internal filter, which will work as a mechanical filter and backup, in case the first one fails. However, avoid strong mixing of water in the aquarium, which would tire the fish. Set the filter outlets so that the water movement is relatively small. Install an aerator as well.
Use roots and stones as decorations. However, definitely avoid sharp elements which could injure fish, especially varieties such as lionhead or telescope. It’s also a good idea to stick the background, preferably black or blue, to the back wall of the aquarium. It will make the tank more appealing.
Lighting does not have to be strong and the plant species suggested below do not have high light requirements. You can use both a cover with a light bar or a hanging or standing lamp over an open tank. However, it is worth remembering that fish also need light because it enhances their coloration.
Gravel with a fine or medium granularity and smooth edges will work well as a substrate. Remember that fish dig through the substrate, so sharp gravel could injure them, and one with too much granularity could lead to choking.
What plants are suitable for aquarium with goldfish?
Goldfish are definitely not the fish for which you will create a typical planted aquarium. First, as you already know, goldfish dig into the substrate, so as a result, the plants get uprooted. Secondly, goldfish enthusiastically diversify their diet with soft-leaf plants. But you don’t have to give up plants. You can choose epiphytic species that are not planted in the substrate, such as microsorum, anubias and bolbitis. This way you will avoid digging problems. In addition, their leaves are tough, so there is a chance that fish will not be interested in them. You can also try planting cryptocorynes or vallis, but protect them from being dug out by covering them with pebbles or planting them in pots. Support plant growth with regular use of Tropical Aquaflorin Potassium and Tropical Ferro-Aktiv.
Water parameters for goldfish
Goldfish are pretty flexible when it comes to chemical parameters of water. However, for their well-being and nice appearance, it is best to provide them with water with a pH of 7.0-7.5 and hardness of 6-15°n. Too hard water can contribute to fin damage, especially in delicate breeds. You can check the basic chemical parameters with the Tropical 6 in 1 strip test. You can also use drop tests: Tropical NO2 Test, Tropical NO3 Test, Tropical GH/KH Test and Tropical pH 6.0-7.8 Test.
Goldfish are cold-water fish. It might seem you could give up a heater in the aquarium. In practice, however, it depends on the ambient temperature and the origin of the fish. If it’s cold at your place, or you buy fish from, say, Thailand, where they live in warm water (27-28°C), get a heater with a thermostat. The temperature in the aquarium with goldfish should be about 20-25°C. When buying pedigree fish, it is best to ask the seller about their requirements.
Companionship
Due to their specific requirements and the risk of other fish biting their long fins, we recommend keeping them in single-species aquariums.
Aquarium care
In a mature aquarium, 30-40% of the water in the tank should be changed every week. The smaller the aquarium, the more likely that water parameters will deteriorate faster. Every tank is different, so you need to work out the frequency of water changes on your own. The determinant can be the concentration of nitrates in the water, which should not exceed 40 mg/l. Treat water for water changes with Tropical Supreme, and then add Tropical Bacto-Active and Tropical Nitri-Active with bacteria.
Foods for goldfish
Goldfish are omnivorous. Their diet should be varied and rich in roughage: fiber and chitin. It is important to avoid overfeeding. You can base their daily diet on multi-ingredient products dedicated to goldfish e.g. Goldfish Color Flakes, Goldfish Colour Pellet, Super Goldfish Mini Sticks. They enhance coloration and ensure proper intestinal peristalsis. Remember to enrich their diet with high-algae e.g. Super Spirulina Forte Granulat, 3-Algae Granulat and immunity-supporting foods e.g. Tropical D-Allio Plus Granulat, Pro Defence size M.
Ph.D.Eng Aleksandra Kwaśniak-Płacheta
