Keeping captive turtles and tortoises growing in a healthy,
natural fashion is an ongoing challenge to turtle keepers in
which vitamin and mineral supplements play a large part.
Turtle keepers must try to balance diet, supplementation and
environmental conditions, and there is no simple formula
that guarantees perfect results for any turtle species.
However, there are some generalizations that hold true for
producing natural, healthy growth in Chelonia, and that is
what we will begin to address in this article.
Since one of the biggest factors in the proper, healthy
growth of turtles is calcium, let's look at it first.
In the wild, turtles get their calcium primarily from eating
plants that were grown in calcium-rich soil and so are high
in calcium. Also, snails are a common wild food of many or
even most turtle species, even desert tortoises, and high
calcium snail shells are usually widely available to turtles
and happily crunched. Water turtles also eat crustaceans
which provide calcium to their diets. Turtles may also snack
on other calcium-rich items such as dried bones.
In captivity, turtles and tortoises aren't likely to get the
same quantity of calcium in the diets provided to them.
Added to this problem is the fact that the foods they are
given are likely to also contain too much phosphorus. Low
calcium and high phosphorus levels is a recipe for health
disorders in any animal, and in turtles can result in severe
deformity of the shell, beak and legs, fragile bones, and
other terrible problems.
So, what can you do to provide a balance of calcium and
phosphorus for your captive turtle?
The answer is two-fold:
Carefully research your turtle species, its natural habitat
and diet, and provide a diet that is as close to the native
diet for your animal as is possible.
You need to make sure that the diet of your turtle or
tortoise includes foods with a high calcium, low phosphorus
ratio. But, one challenge to achieving that balanced diet is
that many plants that are high in calcium also contain
natural chemicals that make it harder for the body to use
the calcium in the vegetable. Most of the very dark green
vegetables (collard greens, kale, cabbage, mustard greens,
spinach, and bok choy, etc.) are included in this group. The
phytic acid found in high concentrations in legumes (peas,
beans, etc.) can also cause the same problem.
So, you will not only need to watch the diet you offer your
turtle to make sure you offer high-calcium foods, but you'll
need to be sure that, as best you can, you don't depend
greatly on calcium-blocking foods. That is hard to do,
especially in the winter, but supplementation can help.
The second thing to do to help your turtle grow properly is
to feed it calcium supplements. In that regard there are
many possible choices. Avoid supplements made from bone
meal, as they will add to the likely already overloaded
phosphorus count in your turtle's diet, but do purchase a
commercial supplement created for reptiles, as they will
have been tested for the unhealthy levels of mercury, lead,
and the like that are sometimes present in bone meal or
If you have many turtles and need large quantities of
supplements, one recommended supplement is limestone powder,
which you should be able to find in bulk at your local farm
feed store. But the best recommendation for supplementing
the diet of your turtle or tortoise is a commercial calcium
carbonate, phosphorus-free powder, possibly with added
vitamin D3. You should be able to find one at your local pet
store, or by searching on the Internet.