Sometimes you have to figure that some people just don't know what they are talking about. The 17 yr old kid at Petco more than likely doesn't know which fish are reef safe and which need special care... he is more concerned with being *****ed out by his manager or other customers. Saying you don't know in retail is a big no no nowadays. It almost seems like lying is an acceptable practise if it gives the customer a needed answer. It is like the instance where the one guy saw a LFS
customer with two clown fish, a 20g tank, and a bag of IO. The clerk told him that it was fine to add salt and then just add teh fish. Obviously the kid was more likely just to not know what he was talking about because no true knowledgable person would recommend such a thing. Heck that kid could have made more money selling all the accessories to the tank instead of the fish. Plus if you think about it the guy still had to buy the fish next time anyways. It was much more likely that the guy would kill the fish and not come back to that store because of the bad service.