Minh,
If your female is pregnant, great! But I've noticed that females generally tend to carry a little more weight than males when the two are paired up, though, so she may just be "heavy-set" and in preparation for breeding. In order to encourage breeding, and for the eggs to be healthy, you need to feed LOTS of good food on a consistent basis. As an aside, I have a pair of my own tank-raised clowns, and my female is rather chunky, but she's not pregnant......or at least I've never seen a batch of eggs anywhere close to where the clowns hang out.
Anyway, if she does happen to lay eggs, she will continue to do so like clockwork, so you need not rush out and get a bunch of stuff and cram to try and learn how to raise the fry. Be patient, read all you can, ask questions, and when you're sure you and the eggs are ready, then go for it. In some instances, the male takes a while to get the hang of taking care of eggs, and you might have several clutches of eggs go bad before you get a clutch that hatches out. It's better to let the male become proficient at getting a clutch to hatch.
Never move the parents from their tank with the eggs. Move only the rock/tile with the eggs, if possible, and do so only at the last hour before hatch. Then you can set up the air line, etc. etc. I would encourage the clowns to lay on a small 4X4 piece of tile set just under the anemone. If no anemone, place the tile at an angle close to where the pair likes to hang out. With any luck, the eggs will be laid on the tile (rough side up, by the way).
Good luck!
