Well first of all clowns don't have ---. The female will lay the eggs then the male will come and fertilize them. What you are seeing is them bnding and forming a pair. You will only know that it's going to happen when they lay eggs. They may lay eggs in 2 weeks, 2 months, 2 years or never. A good indications is that they are preparing or cleaning a rock off. Also you do not need an anemone, but in my opion it does help to make them feel secure.