I was looking at LED lighting for my planted tank and I found Lunar quite by accident. The main stream LED light setups don't even come close. a 24 hour cycle https://www.youtube.com/watch?v=HxfeEzkp7K0 The passing cloud option is just phenomenal! All of this with LEDs that out perform the PAR of others and far cheaper. LEDs have great longevity, with these setups it's so easy to replace a part of the chain rather than forking out for a whole new fitting.
Thank You Simon