Sand is all I use in my tanks now. It's only cloudy if you choose a cloudy type, but there are kinds that aren't - bagged beach sand and pool filter sand, for a start.
In a way it's messy - the waste just sits on the sand so you can see it. In a way it's cleaner - if we see the waste we're more likely to clean it - unlike gravel where it's out of sight and mind.
With two filters running on my tanks there is enough water flow that the waste is actually kicked up from the sand and caught by the filters, and because of this it's actually very low maintenance - I just need to vacuum it off one particular area where it builts up.
