Schools of silversides are enchanting to watch, dancing in the rays of light, with the fish moving in unison as if they are a single creature.  The timing and magnitude of silverside schools varies from year to year,  most summers they are monstrous.  At peak times in Grand Cayman the schools can completely fill the caverns and gullies of divesites like Grouper Grotto and Snapper Hole,  even overflowing across the top of the coral reef.  On these exceptional days these dives are probably the best in the world, as divers not only descend beneath the waves, but then also on into another living liquid of millions of fish.  As you scuba dive and fin forward the school parts in front of you, then engulfs you in a bubble of clear water, entirely and symmetrically encircled by fish. Suddenly a predator bolts through the mass, hoping to catch a straggler, momentarily scattering the silversides before they reform into their sinuous mass. Cayman Summers don’t get any better than this.