Great news! I have my male betta in a 10 gal. with a low 5 in. waterline. The female is floating in a cup, a little fin-nipped after a little excitement. I let her out but it wasn't time, so back in the cup she went. I put her anyway. He is building a bubblenest under a plastic cup. When should I let her out? everything else is great. See my incredible website:www.freewebs.com/jourdy288 NICE!