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I have 2 plate sized RES I adopted from a friend. They are about 6 yrs old. They are quite happy in their large enclosure. They have a pond to swim in and a 12'x25' area to play, bask, whatever. They don't spend much time out of the pond, but seem happy and do come when it is feeding time.
I have recently acquired a smaller turtle, thanks to a neighborhood kid and the creek up the street Once before I had a very small one and the larger turtle bit its leg off and it died a few hours later. Nothing a vet could do. I am new to the turtle thing so want to get info on their habitats. They will all live outside. The baby is in a large pond now that it cannot get out of and the others cannot get into. It is 4 feet above the ground with no access - nothing around it. I need to know what to do about them being separated, how long they should be separate, to what size, etc. The baby turtle seems quite healthy, is eating well and is adorable when basking (kicks its tiny feet out). He'll have a trip to the vet for a complete check up soon.
Should I plan to keep them separate entirely?
Also, I had a 2 foot fence around the enclosure and replaced it with a 3.5 foot (6 inches below ground). I never saw them trying to get out, but I am sure they could have. My husband says it was fine at 2 feet. I'll see if I can post pictures - I know it is hard to imagine.
any advice is appreciated
Thanks

I'd keep the smaller one by himself until he's more the size of the others (which sounds like it could be a while). You also should keep him quarantined for several months at least to help ensure he's healthy.

Waiting for pics.

I am going to try to get pics posted this week. The baby is very active and seems happy. His/her vet appt is Monday so hopefully all will be well.
It will be quite a while before the baby is anywhere near the size of the others so he'll get spoiled separately.