Check this out for clown pics... http://www.liveaquaria.com/product/scateg.cfm?pCatId=27
There are more simple anenomes that don't need a lot of light. I've never had one, but advice given on this board by others say there are some easier ones. They also require other unique care like feeding, water flow, and caution about getting sucked into powerheads. I've heard of'm settling into areas in the tank where they are more hidden.
You can cycle the tank and cure the rock at the same time.
Does everyone agree with this having to wait a year before trying to keep an anenome?
Search some of the threads on the subject. There maybe some who've had earlier anenome experiences but the majority of the discussion is about more mature tanks and after some practive and consistency in maintaning water quality - sometimes described as more difficult to do with only 20g.
Any hope for...say... a larger tank. 40G maybe?
I'd recommend blue/greeen chromis instead of the more territorial damsels anyday. I think 3-4watts per gallon in a simple power compact lighting setup will give you what you need.
Keep us posted on your reading assignment (Fenner) and your selection/decision process as a result.