help me out in what 2 stock

Sorry, it could just be me, but I'm confused - who are you quoting? I'm assuming you're asking what fish you can keep in a 15g with artificial plants. The quote says there are 'freshwater tropical fish' in the tank - what kind, and how many? That will dictate how many more (and what type) you may be able to add. A little clarification will help

I think he/she is quoting him/herself