Turtle tank set-up & lighting
I am planning to use one of Arcadia’s D3 tubes for my young musk turtles.
Can you please tell me which would be the best tube to use – either the D3 or the D3+ tube? The water depth is around 30cm (12in) and the musk turtles stay mostly down at the bottom. I need to know which tube would give enough UVB through the water to benefit my turtles. Have you any care information that you can give me too, please?
The musk turtle (Sternotherus odoratus) is probably one of the best choices as a pet turtle. Its compact size and ease of care make it the perfect subject for life in the home aqua-terrarium. An adult musk will rarely grow bigger than 10cm (4in) in terms of its shell length, and these turtles are not generally aggressive by nature. They are also known as stinkpot turtles because of their ability to emit a distinctive musky odour when they feel threatened, although they soon grow out of this habit once they are used to being handled.
Baby musk turtles are frequently seen in aquatic and reptile outlets all over the country and have a really cute appearance, with hatchlings being around the size of a 20p piece.
They require a very varied diet including small crustaceans and invertebrates – not forgetting plant life. I personally think that including vegetation in the set-up is essential for this species.
“Its compact size and ease of care make it the perfect subject for life in the home aqua-terrarium. An adult musk will rarely grow bigger than 10cm (4in) in terms of its shell length.”
Youngsters will readily eat oxygenating aquarium plants and I have used the new Tetra Fresh Delica Bloodworm pouches very successfully with them. Live bloodworm and small river shrimp are eagerly chased and consumed as well. If a small group of these turtles are housed together, I have even seen them work as a team to drive river shrimp into a corner of the tank so that they can catch and consume these crustaceans more easily.
Proprietary frozen foods are useful as well, being thawed in advance, and JBL make some awesome dry turtle foods.
It has been thought that musk turtles are nocturnal; again I cannot agree with this. They may be more active and feed more hungrily at lower light levels but every healthy individual that I have encountered has been active during the day. These turtles do not seem to leave the water readily though, in order to bask on dry land, but they do spend long periods floating at the surface. Their habit of feeding when light levels are low may simply be a means of avoiding predators.
I suggest that when using a turtle-safe water heater set to around 21-24°C (70-75°F), a heat spot is not required for this species if the water is heated. A dry area should still be provided though, just in case your turtles do decide to leave the water.
With regard to lighting, since musk turtles are not given to long periods of open basking, then a high power combi lamp is not necessarily required. As with other reptiles though, exposure to both UVA and UVB is essential for their well-being. Providing both their natural Vitamin D3 cycle.
As you point out, UV light does not travel very well through water – the results that I have measured suggest maximum penetration of between 7.5-10cm (3-4in). So it is certainly possible that these small turtles fl oat in the wild as they do in a tank, and still benefit from exposure to the sun even if they are a short way under the water. (This is also true of some fish like the Asian arowana (Scleropages formosus) that sunbathe naturally in the wild).
The water level that you have in your tank is actually quite deep for these small turtles though, which often prefer to walk across the bottom rather than actively swimming, so you want to reduce this by about a third in any case.
What you need to consider is the size of the enclosure and the distance between the lamp and animal at the furthest point. UV light does not travel well through air either; as the light has a progressively greater distance to travel, so the emission becomes weaker. The choice of the percentage should always depend on the crucial distance from the lamp to animal, rather than anything else.
If the distance from an unfiltered lamp (meaning there is no glass, plastic or acrylic between the lamp and the animal) is greater than 30cm (12in), use the D3+ 12%. However, if it is 30cm (12in) or less, then the D3 6% will be fine for your musk turtles.
Every species is different though and this interpretation cannot be applied to other reptiles. The use of the correct reflector is the key to success. Fluorescent lamps emit light all around the tube, so that by the nature of their cylindrical design, a lot of this light is wasted. By choosing the correct reflector, you will effectively capture all of this light that would have been wasted and direct it down to where it is most needed on to your animals.
This calculation is only based on the standard output Arcadia brand T8 2.5cm (1in) lamps. If you decide to use the brand new, award-winning, high output T5s, then the D3 6% and reflector is all you need for distances up to 61cm (24in) above the turtles.
As with any enclosure where lighting of any type is used though, the animals must also have access to places of shade and seclusion. For small turtles, floating fake rocks or wood and plenty of plants are very useful to provide seclusion. Please also bear in mind that all light fittings that are intended for use above water must be waterproof. Look for a symbol that says IP67. This is now the law.
© John Courteney-Smith Taken from “Practical Reptile Keeping” magazine