General Care for Aquatic Turtles and Terrapins
Water Area
All species of aquatic turtles love to swim in as large an area as possible. The normal quoted rule is that 38 litres of water are required per inch of shell for the first turtle, then an additional 17 litres per inch of shell for each additional animal. This is a larger volume of water than most people realise, for example a 48"x18"x12" (122 x 46 x 30cm) aquarium, when full, will hold 170 litres (45 US gallons) which would theoretically be enough space for one 4.5" turtle to swim in.
This can be achieved with an aquarium, fibreglass stock tank, large plastic storage tub or pond.
Cohabiting turtles is a risky business, some will advise never to do it, whereas others do it with no issue. To avoid aggression between tank mates you need to provide as large an area as possible and add some decorations to block the view from each other occasionally, and allow the animals to hide. Plastic plants and ceramic plants pots perform this function well.
You will need an aquarium heater to keep the water at 27 degrees Celsius for turtles under a year old. After that 22 degrees is the correct temperature for most species.
At a glance
Water volume = 38 litres (10 US gallons) per inch of shell for first animal + 17 litres (5 US gallons) per inch of shell for each additional animal
Water temperature - 27c for hatchlings under a year, 22c for turtles over a year old
Water Quality
Filtration and Aeration
Turtles are dirty animals, they eat and defecate in their water and produce a far larger amount of waste than fish. Their water will become foul extremely quickly without assistance, this will look unsightly, smell and be dangerous for your pets. Dirty water increases risk of disease and death.
To prevent this, strong filtration is required. Once you know your water volume you need to select a filter. A normal aquarium filter will do with a few extra considerations. Aquarium filters are designed with fish in mind, they will be "rated" for a volume of water. For example, a Fluval 407 external canister filter is rated for up to 500 litres of water. For turtles we need to divide this amount by 3 so it would be suitable for 167 litres of turtle water at a maximum.
I recommend an external canister filter for all but hatchlings.
In addition to filtration, a 25% water change is required per week to remove harmful ammonia from the water.
Air stone bubblers will oxygenate the water and agitate the surface preventing protein buildup which will further improve its quality.
At a glance
Filtration is required at 3 times the amount required for fish.
Perform 25% weekly water change to remove ammonia.
Bubblers oxygenate and improve water quality.
Basking Area
Lighting
All freshwater turtles (with the exception of Fly River Turtles) need an area to haul out of the water and bask. This is important for the turtles to be able to absorb vitamin d3 and utilise it in calcium synthesis. Without this the animal will develop metabolic bone, fungal infections and/or shell rot, all of which can be fatal.
The area needs to be completely dry and can be provided in a number of ways. Commercially available "Turtle Ramps" stick to the side of the tank and float on the water. They make good use of available water but larger turtles will sink them. Piles of stone can be used, but this seems a waste of water area to me, and could topple and injure your pet. Pieces of cork bark are often used. You can also be inventive and build your own. I prefer to build an above tank basking area out of acrylic and aquarium cement to fully maximise my tanks water volume.
Above the baking area it is vital that you provide both UVB and UVA/heat lamps. UVB is more expensive to provide but is essential for the synthesis of calcium as discussed earlier. There are multiple options available for this, screw fit bulbs that fit in a normal lamp holder, or tube fitments which cover the full length of your tank. You need to provide the correct strength of UVB which is normally 5.0 (5%) if your bulb is close, say 6" away or 10.0 (10%) if further away.
The UVB bulb will not usually give out heat, so another lamp is also required. A normal light bulb or ceramic heat emitter will provide the heat required by your turtle. They need to be able to dry off and increase their internal temperature to assist in digesting food and other bodily functions.
There are bulbs on the market that will provide UVB, UVA and heat such as the Arcadia D3 Mecury Vapour Bulbs. These are more expensive and can shatter if water gets on to the surface although I find them much more resilient than their cheaper "heat and light" only bulbs.
The basking area should be kept at around 32-35c
Lights should be on a timer set to 10 - 12 hours light provided per day to mimic natural conditions.
At a glance
UVB and UVA are both essential
Basking area to be kept dry and 32-35c
Nutrition
Feeding your Turtle
As with all animals, variety is the key to a healthy diet. Commercially available dried turtle food, which contains pellets, dried mealworms, shrimp and other things, should form the staple of your turtles diet, but be conscious that this is considered a protein item.
Most species require vegetation too, some more than others. They will eat any live plants that you put in, and they will make a mess doing it! I prefer to buy "mixed salad leaves" in a bag from the supermarket, just make sure that it doesn't contain spinach or iceberg lettuce, as both are toxic to turtles in large quantities.
You can feed your turtle certain fish (not goldfish or other carp related fish) and seafood such as prawns etc. Just be aware that this will make your water oily and too much protein can cause liver issues and pyramiding of the carapace.
Some like to feed their turtle in a separate feeding tank, this will increase the cleanliness of the water and reduce cleaning out, however, can increase stress on the animal. This is something you need to consider.
At a glance
Commercially available turtle food
Mixed salad leaves
Aquatic plants
NO spinach OR iceberg lettuce