So at 2.75", the turtle is a bit too small to be sexed yet. Also, most pet stores cannot sell turtles less than 4" SCL.
Sorry to hear about your saltwater nano

On the flip side, glad to have you on the forum.
I did a 5G high-tech nano for a few years - aquac remora nano hang on skimmer, AC50 converted into a fuge, and LED clamp on lighting. Because it was a 5G tank, I just used the bottled sea water but got bored with it when I didn't have any more room for new fish or coral.
On a good note, turtle keeping is MUCH less expensive than reef with a lot less equipment. You'll need a decent sized tank, and a huge canister filter + a few lights and that's the bulk of the expense. If you buy big up front, the tank and the giant canister become a one time expense. So welcome, have a look around and feel free to post any questions or just hang out and chat
