Keeping turtles and fish in the same tank is possible, but only if a few conditions are met. One of the most important things to consider is that turtles often eat fish. If you intend to ensure that your turtle and fish get along and that your turtle does not mistake the fish for food, it is important to consider the size of the fish and the type of fish. For instance, you probably wouldn’t want to put guppies or goldfish in with a turtle because they are smaller and they also generate too much waste to the water. It is also a good idea to avoid the Oscar fish because instead of your turtle eating the fish, they will most likely end up getting injured from the oscar’s bite. Most pet owners that have fish and turtles in the same tank opt for certain types of catfish, giant Gourani, or cichlids that are not overly aggressive.
If you are planning on housing fish and turtles together another important thing to consider is space. Turtles can grow up to very large sizes and it is quite common for them to reach at least a foot in length. Keeping this in mind, it’s never a bad idea to have a tank setup that is at least 80 gallons of water with the length of the tank measuring in at least 5 feet.
Another thing that is required within a turtle fish tank is a complete filtration system that can handle a large amount of waste generation. External power filters work great especially if you have a fairly large fish. Not providing your turtle and fish with a filtration system will lead to murky and smelly water. It’s also ideal to include an aeration system that is generated by air pump so that your turtle can reside within an oxygen rich environment.
Something else to consider is that turtles require dry land in order to rest, bask, and relax. Therefore your tank should have a part filled with sand or large rocks that are higher than water level. Getting a turtle ramp is also ideal as it has a suction cup that just attaches right to the side of the aquarium wall surface. Many people who try to keep fish and turtles together in the same tank do not realize that turtles need to be able to escape from the water every now and then. If they are unable to do so, you will end up coming home to a dead turtle that has died from exhaustion.