I think my danio is pregnant

Hi, new to this whole fish-keeping thing... bought 5 zebra danios on the weekend and one of them appears to have gotten very fat underneath at the front.. is it likely that this one is pregnant (None of the others are fat like this). If she/(he??) is what do i need to do in order to get her to lay the eggs and then for them to hatch? Any advice would be greatly appreciated. Here's a pic of my tank: is there something suitable on there for her to lay on? Or do i need to put her in a separate tank or something. Thanks guys in advance!!
Thrifty

Just tried taking some photos of it to see if you guys could confirm but the blimen' thing wouldn't stop moving! It looked like she was being chased.... don't know much about courtship but that sounds like what could be happening... Please help!

HI there

ok males are slimmer than females when compaired to females and by your description you have a female.
She is eggbound, as danios are egglayers.
as for breeding them thry this link for a breeding diary I started a week ago.

Checkout my website for infomation on your danios and other types that are available.
If you need any help at all you can pm me or got live chat, I'm online most of the day and in chat a lot as well.
HTH