Male left, female right. 100% sure. Small and nice looking. I'd say ~4 months old. Look for the little lady on the right to start laying eggs soon. If you want to see if she is ready, change about 25-50% of the tank water each day for 3-5 days and you might see a lot more activity such as choosing of spawning location, cleaning surfaces, etc. What is the temp of the tank? I'd keep it at 78-80 degrees. When /if you do the water changes as described above, try slightly cooler water to drop the tank temp down to 76 and that might encourage them even more.