If you can buy clip-on dividers then that would be easiest. My thoughts of making a frame (either wood or metal) to attach netting to was so the water would flow through and you wouldn't need to heat each side and get another filter.
Each compartment will need a heater and filter, unless you have an under tank heatpad along the whole tank, and a flow-on filtration system so the water circulates through the whole tank.
If you are wanting to line breed or encourage a particular colour, then control your impatience and don't get any more colours. You will need a fishroom to cope with all the offspring!