Have folks had angelfish that absolutely, and very specifically, loathe one another? Some background: I got this gold and gold marble as half-dollar-sized younguns at the same time back in February. They were clearly grouchy with each other in their 10 gallon QT tank, but I thought maybe that was an issue of tight quarters. After 6 weeks I added them to my juvie angel tank with my batch of Philippine blues. I'd still see the gold chasing the gold marble to the back of the tank, to the point where I'd only see the marble out front at mealtimes and at night after lights-out. Note that at max, there were 8 other angels in there, none of which got so much attention from the gold. In April the gold (male) paired up with my blue ghost, so I moved them into one side of my divided 60 gallon that I set up for breeding pairs. Since all of the angels were getting towards adult size at this point, I put some of the blues in the other side of the 60 to continue mingling and pairing off. No sweat from the gold and his lady, they went about their business and have laid a couple of clutches of eggs. (Can't get them to not eat them all after 36 hours, but that's a different story...) This weekend, the gold marble (also male!) decided to pair up with a blue zebra, so I did some shuffling and put them in the 60g, divided from the gold and the blue ghost. As soon as the gold realized the gold marble was in the other half, he marched to the divider and began to display his aggravation. As before, he spends a lot more time being angry about it than the marble, but the marble will still waggle his fins at the gold from time to time, too. I don't have another tank to put one pair in at the moment, but I'm going to try to separate them ASAP. It's just a little startling to me how much the gold hates this one fish. XD Is it perhaps because they look a little similar? Is this kind of grudge common?