After this event I was much more careful about choosing fish and coral that were more peaceful, and made sure to QT them for 6 odd weeks, depending on the individual. As expected I had some hiccups over the way.
My favourite is when introducing my melanurus wrasse. She was relatively large compared to the other fish at the time so I didn't expect there to by any trouble. She was swimming and eating fine in the fish shop, and I had been watching her for some time before purchase. She went through QT very well, eating everything. After introduction to the display tank she went straight under the sand (something I hadn't seen before). Surprisingly she didn't reappear during the day for about 10 days. I saw her once at around midnight during this time. Eventually when she came up during the day, she was swimming funnily, and couldn't stay upright and wouldn't eat anything. I couldn't believe it, she was fine during QT and I had treated her for parasitical and bacterial infections. After quick research I discovered it may have been a swim bladder issue, her stomach was very bloated. I fed her green peas (boiled and chopped into edible portions), and within a few hours she had returned to normal.