I have a gold gourami in my 75 gallon and she is about 6" nose to tail, she is very beautiful, and also became territorial with age. She is fine as long as she has an area to herself, in my 75 gallon this area is the size of a 15 gallon tank spatially speaking. Two such gouramis would therefore require roughly twice that at full size, I really do pray that you do get a larger tank for them, it makes me cringe to picture what would happen on it's current course in your tank.