Discus fish and parrot fish are two very different types of fish; that they're equally fascinating to learn about is not all they have in common. Both discus fish and parrot fish are suitable for keeping in a home aquarium. And they are both known for being difficult to look after -- so they're advised for experienced fish keepers only. They're not suited for living together in a tank.
About Discus Fish
Discus fish are a tropical freshwater species found in the Amazon basin, where they live in deep, calm waters. Three distinct subspecies exist: the green discus, the blue discus and the brown discus. The species name of these medium-size fish comes from their flattened bodies, which are discuslike in shape. In the wild, they're either blue, green or brown in color, depending on their subspecies, but there are several other color variations present in domesticated fish.
About Parrot Fish
Parrot fish are large fish. A number of species vary in size from roughly 1 foot to 4 feet. They're mostly found in tropical lagoons or coral reefs in the Indo-Pacific region and the Caribbean sea. They use their beaklike teeth to scrape polyps and algae from rocks and coral. They have a range of possible colors, depending on species, age and gender. Their genders and subsequently their colors can change several times over the course of their lives.
Discus Fish Care
Discus fish require good water quality, so you need a high powered substrate filter that filters 220 to 250 gallons of water per hour. They prefer soft water over hard, so you may need to filter or treat their water before it goes in the tank. Keep the water temperature between 82 and 86 degrees Fahrenheit, and pH between 5.0 and 6.0. Change 30 percent to 40 percent of the water in the tank each week. Feed a quality flake or pellet food once or twice a day to adults or four to five times a day to juveniles. You can also supplement with fresh or frozen brine shrimp and bloodworms.
Parrot Fish Care
Parrot fish need to be kept in a large aquarium. The size will depend on the species you own, but a parrot fish of around 10 inches will need a minimum tank capacity of 100 gallons and a fish of around 20 inches will need a minimum tank capacity of 300 gallons. Water salinity should be between 1.020 and 1.025, pH should be between 8.1 and 8.4, and temperature between 72 and 78 degrees Fahrenheit. Place caves and other hiding places for these fish. They will feed on coral, plankton and algae.
Due to the large size of adult parrot fish, they wouldn't be good tank mates for discus fish, who prefer to be kept with fish smaller than themselves. In addition, parrot fish are marine fish, whereas discus fish are freshwater species, so it wouldn't be viable to keep them in the same aquarium even if they did get along.