:o Hello!!
We have the high school biology class turtle for the summer. He was found
in northern California dazed in a truck of lettuce after being "picked" by the mechanical lettucepicking machine. He ended up at the high school, and moved to Portland with the teacher.He's about 10 years old, shell about 8" long, and I think he's a western chicken turtle, as he looks like the pictures, has long front claws, and a very long neck. He has very faint striping, a very dark green-almost blackish head with very big eyes and a pointed beak. He also hisses loudly and tries to bite whenever he feels bothered. He is also very active and hunts everything. (including lumps of hamburger)
I put some snails in (I think they're mystery snails according to the pet store) of various sizes to help keep the tank cleaner and less green and he keeps herding them like a soccer ball and biting diamond shaped holes in their shells. So far he's killed two, and since he was wild, will he always hunt them even if he's well-fed? (you know, like the cat goes after birds because of instinct not hunger) This morning we found little mini snails, so I don't know how to keep them safe. Right now the snails are around the filter with a rock barricade blocking direct access from the turtle. (He would have to almost stand on his head in the water to fish out a snail, and there are 4 various sized adults, and at least 3 babies that we could spot.) I know it's nature and all, but I hate to have him terrorize them for sport, as the ones he killed he didn't eat. They were just dead on the bottom of the tank. Any info you have would be most appreciated, as I learned a lot about turtles, but not much about snails. Thank you for the chance to ask questions without feeling like an idiot doing so!
(The pet store people were very patronizing, so I went on line looking for help and
this appears to be exactly what I needed to find for answers! )
......Fosterturtlemama

I'm afraid that the turtle you have enjoys eating snails. There's no way to make him leave them alone. If you provide some hiding places for the snails, some may avoid being eaten/killed. Even if he's not hungry, he will try to kill any snails he finds.

Only water changes and cleaning the tank can help keep it cleaner. I have a small turtle in a 20 gallon tank with 10 gallons of water with a filter. While he's much smaller than the one that you have, my turtle's water is filthy by the middle of the week. I only have time to do a 100% water change and cleaning on Saturday. Most of that filth would also harm snails and not provide food for them. How big is the tank the turtle is in? What kind of filter? A larger tank and filter will help more than anything.

Thanks for the info Robyn. The turtle is in a 30 gallon tank that is filled about a third of the way. I change the water twice a week, and have a small electric filter with a carbon inset and sponges that I clean each time. Right now the water temperature is about 70 degrees, so he seems pretty comfy. He also has an inch or so of small assorted color gravel that he moves around and settles into. Thats why we were so surprised to find little snails as they looked like part of the gravel. There are a series of larger rocks that form an island with a flat basking rock that he sits on. The filter (and the snails) are at the far end of the tank which blocks most of his access to the snails. They get in trouble when they venture out beyond the rocks into "open water". He is in the corner of our living room that has two large bay windows that get the east rising sun until about 11am, so he warms up well, but all the sunlight started plant growth and the pet store suggested the snails to help. So far he's just maimed them until they've died, so I don't know if he really wants to eat them, or just play with them. When they are obviously dead I've taken them out of the tank, so I don't know if I should leave them for him to see (they do smell pretty rank quickly) or continue to take them out. Also, I wasn't planning to buy him any new "playmates", but because he isn't a usual pet turtle species I don't know much else about what he should be doing or not. The teacher told my daughter that she might let us keep him as she already has multiple turtles in her classroom, but she did say that he shared a tank with other fish including a fairly large catfish and she never mentioned him harming anything in the tank with him. It's been a very rewarding summer watching
him and I've learned a huge amount, but I still don't know more then just basics.
You are definitely the expert, so if you can send me any tips I would really be
thankful. One question I do have, I cannot seem to get him to eat on a regular basis
anything else but protein. He eats (with gusto) raw hamburger, cooked chicken,
turtle pellets, scallops, shrimp, and any other meat, but only nibbles at any lettuce,
veggies, or fruits I've put in the tank. Any suggestions? Thanks again
Fosterturtlemama

I'm not an expert. I just have one turtle and had two previously short term before releasing them and have had wild box turtles visit (and cared for them from time to time).

The little snails could hide in gravel. I didn't think of that. I don't have gravel in my turtle's tank as it makes cleaning a lot easier, and he can find the food easier and not eat gravel. Your turtle needs a bigger tank. A 120 gallon would be great (I have one with my lizard where my turtle will go when my lizard passes on) but anything larger is better. 40 gallon breeders are nice with a good surface area.

I haven't had much algae grow in my turtle's tank since I do a 100% cleaning weekly. Direct sun though will make algae grow more.

I would remove the mangled snails say once a day but not immediately because it would be nice if he at least ate some of his victims.

I'm not familiar with chicken turtles but I think they eat animal and plant matter about equally (like my turtle, a red-bellied turtle which is also in the cooter family). I alternate days of feeding animal matter with plant matter. Every other day, he gets some grated carrot, half a grape, a small piece of apple, and his favorite, a piece of kale. He'll also eat parsley, spinach, arugula, dill, and other greens. Some turtles just never want to eat their fruits and veggies! If you don't offer animal food that day, he may be more apt to eat those things. My turtle loves to gnaw on a cuttlebone and eats live mealworms, waxworms, and crickets as well as half a dozen commercial turtle sticks and treats. Raw hamburger can be risky (bacteria) so I haven't tried that.

My page on feeding turtles - http://www.fishpondinfo.com/turtles/turfeed.htm

Snails are turtle food, probably no way you'll prevent a wild turtle from eating fresh seafood! I'm not familiar with your breed, but snails sound like crunchy sushi delicacies.........tTry those glass cleaning fish (picosthymus?) (sp?), they are excellent at keeping algal growth down, and grow to the size of the tank, I doubt the turtle will bother one.....I don't think they're expensive, and I don't think they require much care or food.....

I don't think it's a good idea to keep plecostomus with turtles. The turtles may nip at them but, more likely, the plecos will not do well with all the turtle waste and mess. Plecos do not grow to the size of the tank although smaller tanks will stunt them. Plecos require as much (if not a little more) care as other fish. They can eat some algae but usually need their own foods as well. Plecos make a lot of waste so a tank will usually get dirtier (not cleaner) in general with a pleco in it. Common plecos grow 1-2 feet long and should be in large fish tanks.