They can usually get along with most fish but sometimes turn aggressive when they get older especially when they live in small tanks.
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Koi are a cold water fish as are Sturgeon. Plecostomus are a tropical fish so they should not be kept together in the first place. Plecostomus are a large but peacefull algae eating fish and they are no real threat to any other fish.
Yes they need them to breath underwater like any other fish.
the Tripod fish is from the dinosaur age and is guessed to be in the Juarrassic period the tripod fish lives in deep sea areas
There isn't any kind of shark in the Amazon river. There is a kind of dolphin. Sharks are sea fish.
Oscars should be kept alone so they don't eat any of your other fish of fight with other Oscars. Oscars also grow very fast and as they do they become more and more aggressive. They can sometimes be kept with a large plecostomus if your tank has plenty of room.
A special cross between fish and turtles, called fitles can live with either turtles or fish. You can buy them in any good persian-sea retailer.
it live like any other fish
None ,any fish really should kept in 10 galls or more despite what common population culture depicts.
No they will not survive the winter in most any place in the US if they are outside. They prefer the water to be from about 72-82 degrees Fahrenheit.
Actually it depends on what kind of fish it is.
Any kind of fish that swims in front of them while they are hungry
No, if they could they would die because they would not be in water. _______________________________________________________________________ Yes, Plecos can jump out of your tank. Nearly any fish can. A glass top that sufficiently covers the the top should prevent this.