I have a question about Black Convicts. I bought a female convict about a few weeks ago. She had a bit of pink on her, but she mostly had dark stripes on her. When she got into my brother's tank, her stripes faded, and her pink belly became more prominant. I bought a male today (no pink on him, right?). He was almost jet black...his stripes were very black and prominant. A half an hour after I put him into my tank, his stripes faded, as well. Now he has light grey stripes. My question is what causes this, and how can I get their stripes back?