Catching
Catching a painted turtle is illegal in some places, so you might want to check the area you live in before you try to get one. If you can, find a small lake on a nice sunny day, grab a net with a long handle, and begin to make your way around the lake, trying to stay low so your future pet doesn’t spot you before you are close enough. Turtles seem to be more vulnerable early in the day before they have had a chance to warm up.
Like all reptiles they are cold blooded, so they are sluggish in the cool morning air. You’ll have to look hard because turtles have evolved to blend into the plants and leaf litter, not to mention that wild turtles have algae growing on their shells. Try looking at reeds about a foot into the water, or on the bank.
Once you do spot the turtle, crouch even lower and move very slowly so you don’t spook it. Once your in range, throw the net over the turtle. If it’s in the water already, throw the net downward in front of the turtle and pull it towards you. The turtle will try to swim into deeper water and will go right into the net. Once you have him, you can carry him back in the net; he will tuck into his shell, so he won’t get hurt.
Housing
All aquatic turtles need water in order to stay happy and healthy; they also like to eat under water. The minimum depth of water is as high as the turtle is wide so that it can move freely, but I recommend giving it as much water as you can. Aquatic turtle spend most of their life in the water, and they are far more agile while swimming. This isn’t to say that they don’t need a place to climb out though.
Most pet stores have little ramps and docks that attach to the aquarium with suction cups. These work rather well. You should also put some fake plants in the bottom to make your pet feel more at home. I don’t recommend real plants as aquatic turtles are very active, and they will even eat the plants since they are a part of a turtles diet. You will, however, need a heating light with UV rays.
Turtles need sunlight to grow their shells, but glass can block out these rays, so you will need to get a heat lamp and light at your pet store ( make sure it says it emits these light rays). Place this over your turtle’s floating dock so that it can bask and relax. You will also need a filter, maybe even two depending on the size of the tank and turtle. You can also add a few items at the bottom of the tank; turtles like to peek their heads out of the water while anchoring themselves with their hind legs.
A lid is only required if your dock is less than the turtles body length from the top. Turtles are surprisingly good climbers (I even once found a small painted turtle in a tree!)
Feeding
Turtles are predators during their younger years, but switch to a mostly vegetarian diet in their older age, so what you feed it will depend on the turtle you have.
Earthworms, large beetles and small fish are great for a youngster, but you can still give them the store bought turtle pellets to round out the diet (they need the vitamin d supplement to stay healthy). Older turtles have larger appetites and may still eat meat, so I don’t recommend keeping any expensive fish with them. Some people might find feeding turtle live fish as barbaric, but this is how they eat in the wild and it gives them much needed exercises. It also makes the tank seem less empty.
Keep in mind that if you do keep fish in the tank you will need something to keep it oxygenated, and turtles are very messy eaters, so you will have to scoop fish parts out with a net every now and then. Turtles can also eat bits of ham and such, but that isn’t really a part of their diet. In fact they will eat almost anything that moves. Older ones “should” eat lettuce and vegetables, but they might be picky, so you’ll have to find out what yours likes.
Cleaning
A turtles tank needs to be cleaned at least once a week; it helps to set aside a day for it. You need to clean out the filter and occasionally replace the water. Once in a while you will need to rinse off the small rocks that line to bottom of the tank as the bits of filth with collect there. If you have an algae problem growing on the glass DO NOT BUY A SUCKER FISH! Your turtle will kill it before it does any good. Instead, you need to get a squeegee to scrub it off.
While you are cleaning the tank, you can put your turtle in the tub, or better yet, outside where it can get some real sun and stretch its legs a bit, just make sure it‘s in an enclosed space and it can‘t run off. Refill the tank with cool, but not cold water, and place your turtle on the dock so it can go into the water on its own.
Handling
Sadly, many reptile pets including turtles can carry salmonella, so you should make sure to thoroughly clean you hands after handling them or their water. They can also be aggressive, so keep you hands away from their face or they may bite you.
When picking up a turtle, try to get a hold of the turtle form behind, if you grab them by the side, their legs can get a grip on you and scratch you; large turtles have pretty sharp claws.
Other Considerations
Turtles can be territorial animals, so you don’t NEED to put several of them together, but they shouldn’t kill each other if you do, though you may need to separate them during feeding.
Most turtles settle their disputes by doing a funny display underwater where they wiggle their claws at each other, sounds strange I know. Mating is ironically more violent; the male will bite the female around the head. If you have a mating pair and the female is pregnant, you need to give her a place to lay her eggs, or she will lay them in the water and they will die. A small area with loose soil and mulch should do nicely. Just put her there at night as that seems to be the time they lay their eggs. Keep this little spot nice and warm, but not hot, and in a few months you should have a bunch of little turtles.
I really recommend you release these where you caught the parent though, as rearing baby turtles is pretty hard; they have a high mortality rate. Turtles also need vitamin D which most turtle pellet food contains, but without it the turtle’s eyes will grow shut and it can die. And finally, make sure you take your turtle out of the tank and let it walk around every now and then, they need the exercise.