ask for what you think they are worth. A while ago i sold a stunning red rose discus, and asked for $200 on here. no real bites, and it lasted a whole 20 minutes on trademe after I listed it. someone accepted my buy now.
I *think you have melons IIRC.
I'm thinking maybe the 120+ mark for a good non stunted well grown specimen that is relatively large - on trademe, less on here.