Hello iv got a 60ltr Tetra tank I started over two years ago. I had keeped goldfish befor and still do but this was my first go at tropical fish. I set it up and over the proper time added guppies I added male and female guppies as I wanted them to breed and have fry. My tanks ran very well and over time I have leaned loads not with out some small problems to deal with but thats all part of fish keeping. Now after two years every thing is going really well but I want to start keeping other fish but guppies just dont stop breeding and breeding and without room for a nother tank how do I change from guppies to other fish? Thanks