Special equipment You will probably want to get some special equipment to keep the water of the aquarium healthy for your turtle. A filter cleaning out waste products is a good investment, especially if you are a beginner, since it makes the aquarium much easier to maintain. Filters are not absolutely necessary, but if you choose to pass up on filtration you will have to clean the aquarium once every few days. If the waste products are not removed by filtration or cleaning the water quality will deteriorate and your turtle will be weaken and less able to resist bacteria and fungus infections. If your tank is less than 25 gallons (100 litres) we recommend an internal powerfilter. If its bigger, a canister filter is usually the best solution.
Special aquarium lighting is not necessary, but the turtles will appreciate it and do better if you provide them with it since they need light to synthesis vitamin D. If you feed them a proper diet they will get vitamin D from their food too, but sometimes that is not enough. If you dont use aquarium lighting place the turtle aquarium in a sunny spot at least twice a week, or give it a permanent place where it will receive some diffuse sunlight every day.
Some turtle aquariums will also require a heater to keep the water temperatures optimal, but this is of course depending on the temperature in the room where you keep your turtle. Freshwater turtles prefer 22°C to 26°C, but anything from 20°C to 28°C is okay. Use an aquarium thermometer to check the temperatures daily. Whether the thermometer is a the floating or the stick-on variant doesnt really matter. The temperature should never be allowed drop below 20°C since most freshwater turtles will stop eating at this temperature. Even if they dont starve to death, they will be weaken by the lack of energy and more prone to catch diseases. If your turtles keep on eating even though the temperature is below 20°C they risk developing intestinal gangrene since the food is not digested properly at such a low temperature. Intestinal gangrene is a very serious and often lethal condition. The most critical temperature for your turtles is between 12°C and 20°C. If it gets any colder, the turtles will simply go into hibernation. Most turtles will survive hibernation, but baby turtles are sensitive since they have not yet developed sufficient fat reserves and might starve to death. You should therefore never allow your young turtles to hibernate. Temperatures below 12°C are not very likely to occur indoors without you noticing it, but there is always the risk of power outage if your home is electrically heated. To high temperatures can be as just as dangerous as to low ones, since the metabolism of turtle is dependent on correct temperatures. The metabolism increases when the turtle becomes warm, and temperatures over 28°C can lead to sudden death. To high temperatures can also cause shell damage and fungal infections can start to thrive on the damaged shell. To avoid temperatures over 28°C, turn off any lighting when the weather is warm and remove the aquarium from direct sunlight. If this is not enough, try exchanging some of the water with cooler water. In extreme situations you might even have to add a few ice cubes to the aquarium or direct a breeze across the water surface. Try to avoid drastic temperature changes.