Which fish should never be kept together?

Knowing how to identify incompatible fish pairings can save all lives in your aquarium. Some fish become too aggressive and feel threatened when they encounter shark fin soup among their tank mates. Predators wait stealthily, pouncing on their smaller tankmates for the kill. Some don't get along, while mixing two water currents makes a tangling mess. Other fish breeds can result in slow poisoning due to differences in their environment.

Predator-prey dynamics pose immediate danger. Oscars and other large-mouthed fish instinctively attack small fish. Lionfish prowling for shrimp and little gobies. Be aware of mouth sizes when mixing fish. If one will fit in another, it becomes food in a matter of days.

Clashing temperaments - Although it is not something you see, their constant bickering causes invisible suffering. Semi-aggressive fish incessantly worry others. Bettas suffer fin rot due to barbs. Timid fish cease feeding when they are worried. Watch for signs of chasing or hiding within 72 hours of bringing pairs home, using this as a gauge of their compatibility.

Environmental mismatches kill fish slowly. Goldfish require a temperature of 60-70°F while tropical species typically require a range of 72-82°F. A soft-water tetra will not survive in the hard water of a cichlid. It is essential to test your water temperature and pH levels on a weekly basis. Never add a new fish species to the mix unless you can adjust core parameter requirements.

Use compatibility charts for disaster prevention, and research new fish species before purchasing. Quarantine new fish for at least two weeks. Introduce during evening feeding time. Rearrange tank decor to disrupt territory. Your watch makes safe communities.

Read the full article: Fish Compatibility Chart Ultimate Guide