Yep, the corals with the fluoresent pigments are really nice under actinic lighting, but, and I dont mean to sound like Im telling you what to do, corals do better under lighting of a higher par lower spectrum. Many may survive with hihger K ratings but hard for them to thrive. Unless you are going to limit yourself to only corals that dont require strong lighting. Also and this is as always OMO. You will loose the natural overall beauty of the rest or other corals under a 20000k. Most just look darkend and drab.
I feel a 14000k will give you the best of both worlds and the corals as well.
Just some facts I found if your intrested. //
The zooxanthellae are the golden brown to brown colored algae that are found in the inner tissue layer of corals. They are responsible for the brownish coloration of many corals, and when coral bleach, their skeleton turns white from the expulsion of these tiny protist algae.
The fluorescing proteins, once thought to be only of the green type, are now found in at least eleven colors/types, including, orange, yellow, pink, and red. They appear to be mostly located in the animal tissue, near to the zooxanthellae, and may have numerous roles only now being investigated. The green fluorescing proteins are thought to absorb light of the near UV range and reflect it back to the zooxanthellae in a wavelength they can use in photosynthesis. They may also be used in quenching in high light environments and serve a sort of photoprotective role.
The animal biochromes are those which are found in the animal itself and serve no obvious light-related role. They are probably entirely obtained by diet, and give corals their many brightly colored hues. As corals are sessile animals, they serve no obvious role in display or mating, but may serve in mimicry or warning coloration. This is nicely seen in the symbiotic relationships with some zoanthids and sponges. Other roles of coral color are not well established.
HTH. BTW, is this the Jawfish tank ? Hows it doing ?
I hope you get some good activity in that DSB once the rock is out. Diatoms will pass in time. What do you have in there for snails?