Some freshwater fish cannot live together because they have different water requirements, temperament, size, or diet. These factors can affect the compatibility and harmony of the fish tank, and may lead to stress, disease, or aggression among the fish. In this article, we will explore some of the common types of freshwater fish that cannot live together, and why they are not suitable for each other.
One of the most important aspects of keeping a fish tank is maintaining the optimal water conditions for the fish. Different fish have different preferences for the temperature, pH, hardness, and cleanliness of the water. If the water requirements of the fish are not compatible, they may suffer from poor health, reduced immunity, or even death.
For example, goldfish are cold-water fish that prefer temperatures between 65°F and 75°F, and can tolerate a wide range of pH and hardness levels. However, tropical fish such as guppies, tetras, angelfish, and betta fish are warm-water fish that prefer temperatures between 75°F and 85°F, and require a stable pH and hardness level. Mixing goldfish with tropical fish can result in either the goldfish being too warm or the tropical fish being too cold, which can stress them out and make them prone to diseases.
Another example is discus fish, which are very sensitive and demanding fish that require soft, acidic, and warm water, with a temperature of 82°F to 88°F, a pH of 5.5 to 6.5, and a hardness of 1 to 4 dGH. They also need frequent water changes and high filtration to keep the water quality high. However, cichlids are hardy and adaptable fish that can live in a variety of water conditions, with a temperature of 72°F to 82°F, a pH of 6.0 to 8.0, and a hardness of 5 to 15 dGH. They also produce a lot of waste and can tolerate lower water quality. Mixing discus fish with cichlids can result in either the discus fish being exposed to poor water quality or the cichlids being exposed to water that is too soft, acidic, or warm for them.
Another factor that affects the compatibility of freshwater fish is their temperament, or personality. Some fish are peaceful and friendly, while others are aggressive and territorial. If the temperament of the fish are not compatible, they may fight with each other, chase each other, or bully each other. This can cause stress, injury, or death to the fish, and disrupt the balance of the fish tank.
For example, bettas are known for their beautiful colors and fins, but they are also very aggressive and territorial fish that will attack any fish that they perceive as a threat or a rival. They are especially hostile towards other bettas, or fish that have similar colors or shapes to them. Therefore, bettas should not be kept with other bettas, or fish that have long fins, bright colors, or similar body shapes, such as gouramis, angelfish, or fancy guppies.
Another example is red-tailed sharks, which are attractive and active fish that have a black body and a red tail. However, they are also very aggressive and territorial fish that will chase and harass any fish that enter their territory, which can be the entire bottom of the tank. They are especially intolerant of other red-tailed sharks, or fish that have similar colors or shapes to them, such as rainbow sharks, albino sharks, or bala sharks.
Size
Another factor that affects the compatibility of freshwater fish is their size, or how big they grow. Some fish are small and stay small, while others are large and grow large. If the size of the fish are not compatible, they may compete for space, food, or resources, or they may prey on each other. This can cause starvation, overcrowding, or predation to the fish, and affect the stability of the fish tank.
For example, neon tetras are small and colorful fish that grow up to 1.5 inches in length. They are peaceful and schooling fish that like to swim in groups of six or more. However, oscar fish are large and voracious fish that grow up to 14 inches in length. They are aggressive and predatory fish that will eat anything that fits in their mouth, including neon tetras. Therefore, neon tetras should not be kept with oscar fish, or any fish that are much larger or smaller than them.
Another example is common plecos, which are popular and useful fish that help keep the tank clean by eating algae and leftover food. However, they are also very large and messy fish that grow up to 24 inches in length. They produce a lot of waste and need a lot of space and filtration to thrive. They can also damage or eat the plants and decorations in the tank, or suck on the slime coat of other fish. Therefore, common plecos should not be kept with small or delicate fish, or in tanks that are less than 100 gallons in size.
Diet
Another factor that affects the compatibility of freshwater fish is their diet, or what they eat. Some fish are herbivores and eat plants, algae, or vegetables, while others are carnivores and eat meat, insects, or worms. Some fish are omnivores and eat both plants and animals. If the diet of the fish are not compatible, they may compete for food, or they may eat each other’s food, which can affect their nutrition and health.
For example, goldfish are omnivorous fish that eat both plants and animals. They have a high appetite and will eat anything that they can find, including flakes, pellets, live foods, frozen foods, vegetables, and fruits. However, snails are herbivorous animals that eat plants, algae, or vegetables. They have a low metabolism and will eat slowly and sparingly, mainly algae, lettuce, or cucumber. Mixing goldfish with snails can result in either the goldfish eating the snails, or the goldfish eating the snails’ food, which can deprive the snails of their nutrition and food source.
Another example is angelfish, which are carnivorous fish that eat meat, insects, or worms. They have a high protein requirement and will eat flakes, pellets, live foods, frozen foods, or bloodworms. However, live plants are photosynthetic organisms that produce oxygen and absorb carbon dioxide. They have a low maintenance requirement and will grow well under adequate lighting, substrate, and fertilizer. Mixing angelfish with live plants can result in either the angelfish eating the live plants, or the angelfish uprooting or damaging the live plants, which can affect the aesthetics and health of the plants.
Conclusion
In conclusion, some freshwater fish cannot live together because they have different water requirements, temperament, size, or diet. These factors can affect the compatibility and harmony of the fish tank, and may lead to stress, disease, or aggression among the fish. Therefore, it is important to research the characteristics and needs of the fish before adding them to the tank, and to choose fish that are compatible with each other. This will ensure a healthy, happy, and beautiful fish tank for both the fish and the owner.
