The only thing I could see possible other than this guy being a complete dullard is that maybe someone told him it was a first gen Red Texas, which some say is a flowerhorn, but this guy would have to be really thick to think that is a RT. It is a decent price if you ask me and a good looking texas, but If he still doesn't believe you, show him some pictures with the name on it or show him aquamojo's site, he has wicked pictures of escondidos. Otherwise call him a jackass and find a real FH.
