How to keep grass goldfish? Feeding methods and key points of daily management

Grass goldfish, commonly known as red crucian carp or golden crucian carp, has a strong constitution, strong adaptability and a wide range of foods, and is easy to keep. Besides red, its body color also includes red-and-white variegated and calico patterns. It is suitable for large-scale rearing in parks and natural waters, and can also be kept in courtyard tanks and ponds as well as in aquariums. Now let us take a look at how to keep grass goldfish.

How big can grass goldfish grow?

The golden crucian carp has a robust constitution, strong resistance and adaptability, a wide range of foods, requires no refined management and is simple to keep; when kept in a pond, if food is abundant, it grows quickly, and at three years of age it can reach a body weight of more than 500 g and a body length of about 30 cm, with a maximum length of up to 50 cm.

How long do grass goldfish live?

The lifespan of grass goldfish mainly depends on the environmental conditions of rearing. Generally speaking, with a suitable rearing environment, the average lifespan of grass goldfish is 10 years.

What food do grass goldfish eat?

1. Animal-based bait

① Water fleas: commonly known as fish worms. They are arthropods, and their body colors include brown, reddish brown, gray and green. Fish worms grow seasonally and are divided into summer worms and winter worms. Summer worms breed in large numbers around Qingming Festival, have a blood-red body color, are relatively large and numerous, and have extremely high nutritional value; they mostly live in flowing river water. Winter worms are fewer in number, have a bluish-gray body color and lower nutritional value; they mostly live in still-water ponds or lakes. Fish worms are the main bait for freshwater ornamental fish, and goldfish and tropical fish feed on them throughout their lives.

② Water earthworms: also known as red thread worms or red line worms, they belong to the aquatic oligochaetes among annelids, and their body color is bright red or bluish gray. They mostly live in the mud on the banks of river basins or on river bottoms, densely gathered on the surface layer of the mud, with one end fixed in the mud and the other end protruding from the mud and quivering in the water; upon the slightest disturbance, they immediately retract into the mud. Water earthworms have extremely high nutritional value and must be rinsed repeatedly in clean water before feeding. They are a bait greatly loved by goldfish and koi, and are also the main bait for eel fry. In the Huangpu River in Shanghai, after the river tide recedes, large numbers of water earthworms grow in the mud along the banks, and every spring and autumn people catch them in large quantities.

2. Plant-based bait

① Duckweed: commonly known as rootless duckweed or large spherical algae, it is a perennial floating plant that lives for many years in still-water ponds or rivers. According to relevant sources, dried duckweed contains up to 45% protein and also contains various vitamins and the trace element cobalt; it is a supplementary bait for freshwater ornamental fish. Every autumn, therefore, when fish worms are scarce, duckweed is often used as a substitute bait.

② Chlorella: Chlorella has a bright green body color and individuals closely resemble foxtail millet of the north, each grain about the size of a millet grain. It contains relatively high protein, fat, vitamins and trace elements, has extremely high nutritional value, and is a relatively good green feed for goldfish. If mixed with animal-based feed and fed together, it can effectively promote the rapid growth of fish. Chlorella mostly lives in still-water ponds or small rivers, and it mostly grows together with duckweed; natural waters where Chlorella grows alone are relatively rare.

③ Planktonic marine algae: there are many kinds of planktonic marine algae, including golden algae, yellow-green algae, dinoflagellates, diatoms, euglenoids, green algae and blue-green algae, some of which are supplementary bait for ornamental fish. According to relevant sources, green water or blue water containing algae can be used to feed fish fry, and the effect is also very good.

3. Artificial pelleted feed

In view of the seasonality and unstable quantity of natural bait for fish, which restricts the normal survival and development of fish, processed fish bait came into being. According to the fish species, size and growth needs at different stages, they reasonably arrange nutritional ingredient formulas, adopt mechanized production lines, and carry out processing, shaping and drying in one continuous flow, producing pelleted feed of various specifications with comprehensive nutrition that can fully replace natural bait. Common raw materials for artificial pelleted feed include fish meal, silkworm pupa meal, barley meal, bran, yeast powder, vitamins and green feed, which are mixed in certain proportions and processed into pelleted feed of various sizes. Artificial pelleted feed is a supplementary bait for goldfish, the best substitute when natural bait is in short supply, and also the main bait for red crucian carp and koi.