Here is some info I was able to dig up on short notice out of Scott Michaels Reef fishes "While a coral reef ecosystem, as a whole, may be more stable than many other aquatic or terrestrial biomes, parameters such as light level, temeprature, salinity, water movement, water quality and substrate type can vary in time and space- from tide to tide, from one niche or habitat to the next- on the very same reef as well as from one reef to another"
another- "The temperature on the Heron island reef flat may increase 6c (11 degrees F) during low tide. Temperature changes are often sudden, when the cooler water from the fore reef irrigates the reef flat at high tide.
OK the fish stuff I found involved yellow tangs when I saw it before on another site. There is another mention here involving Yellow Longnose Butterflies doing the same thing. Um just read Reef fishes, there are several pages dedicated to temperature and the whys of keeping it cool. A good example was used, a jeweled damselfish at 77F bit the substrate 225 times while at 82F it bit it 425 times for a 52% increase in food comsumption.
It also mentions parasites not reproducing as well in cooler water. Fish also do not grow as fast, and some fish are less aggressive at cooler temps. The book is way more interesting than I am though.
