When I first got my tank, I was driving by and saw a random fish store. I had my fiancé with me and we decided to pop in and take a look. She found a chocolate chip starfish and really wanted to get it for my tank. My tank was fairly young but already had corals. It was cheap so I told her if it’s reef safe we can get it. We asked the fish keeper and was assured that it was reef safe and we should have no problems. So I bought it. Luckily at my next trip to my lfs I showed my normal fish keeper a photo and he immediately told me it was not reef safe. Needless to say, I ended up donating it and I believe he became Harlequin shrimp food.
i have heard that some* fish stores will say anything to make a sale. But I blame my self for the impulse buy, and should have done my own research. That was a cheap lesson, but since then I do my own research before any purchase. (Thank you reef2reef!)