I will tell you what little experience I have with red eared sliders. My son put two in the pond when it was new (August 2005). I saw them basking in the sun on many occasions and fell for them also. My grandson named them Pebbles and Bam Bam. They are both about the same size so very difficult to tell apart. Last spring about this time of year my neighbor brought one of them home to me saying he found the little critter in his front yard wandering happily in the grass. I put it back in the pond and low and behold next day same thing. I then asked for help on the forum and was told that some of these little critters tend to do this at mating season. I found a local guy who considers himself a turtle expert and he too confirmed that saying if they want to get out they will and there is not much you can do about discouraging it except putting them in an aquarium for the season. Out I went and bought a cheap aquarium and uv light and rock to bask on. I kept the wanderer in there for a couple of weeks after finding him walking down the sidewalk of my yard headed for the front gate Then it started getting a fungus on its shell and I figured I was doing it more harm than good so I put it back in the pond. I thought this time if it got out there wasn't much I could do and it was just the way things go. I didn't see it again for almost a year and had given up on it thinking it had found a new home somewhere even though I live in the city. Then one day not too long ago there were two turtles out sunbathing again and have been almost everyday since. I had seen one on several occasions in the past but maybe they were just taking turns showing themselves to confuse me. It doesn't take much you know. Anyhow that is my experience with them and hope in some little way it helps.

Here is a link that might be useful: My pond the way it was before the freeze.

5 months? Not so baby anymore. Are you feeding Reptomin sticks and earthworms? Minnows? Yum. You may need to crumble the stick till they can handle a whole one. That's all the Baby sticks are anyway.

They will eat any sick fish or bug they can swim after. They do not seek out fish the way Snappers do.

Here's a very classy way to keep your Terrapins contained.

http://www.americansyntheticoil.com/pondw07/ Click pics to zoom.

My 2 boys are about 6 inches and cannot scale the short decorative fencing.

I realize that you did not intend to have a turtle pen however, this is what you must do till they are too large to make it through the big fence surrounding the yard. Maybe add some rabbit fencing at the bottom. It is your responsibility to care for them the best way you can. No body wants to hear that a dog ate a turtle or a car ran them over. Coons and large birds love little turtles.

No matter what lamps you use, you cannot insure a proper environment.

Keep them outside all year and bring them in when the ponds first freeze. Keep them in a few inches of water inside 5 gallon pails in an area where it stays below 50 F and dark. If it gets above 50 they will need to eat. Below 50 and they will hibernate.

Fungi? Use some white vinegar. Eye problems, use Boric Acis as found in Eye wash. Seek a Herp Vet if any issue persists.

Only release them in the deep south. Never release a turtle that is not native.