The males have a much longer tail almost as like a fifth leg and 'barbs' on their knees and are smaller overall. Sex cannot be determined until they are older. Be warned though they may not get on even if two females and can give a nasty bite.
Do ask any questions you need to regarding their care - no gravel, open topped tank, shallow water whilst young with resting places, external filter etc.
Great thanks. They have been together for some significant amount of time in fairly poor conditions. They could be anywhere from 5-20 yo tbh...
They were in a gravel bottomed tank without basking spots or anything else, probably very poor diet and feeding regime so they are survivors!
This is their current set up, got a heat lamp arriving today and are going to add better basking zones but apart from that this is what I was thinking. Any suggestions welcome. I was going to add some substrate but maybe thats not required, and I'm happy with glass bottomed from a cleaning perspective ;o)