The best sand cleaner, and mostly overlooked, is the sea cucumber. It eats sand looking for bacteria and algae and clean sand comes out the other end. They can cover a pretty good range overnight.
Sand sifting gobies are fine but they spit sand. Worse, they eat the fauna from the sand. The helpful micro animals in your sand bed are removed. Sand sifting stars are the same. They will destroy the micro fauna. In fact I think they can starve to death if the tank is too small or there are too many.
A few other inverts are good because they’re sand movers, like nassarius snails and conches. But the aren’t necessarily cleaning.
Don’t remove bristle worms; great cleaners. After my first reef tank a couple decades ago I’ve never had an issue with detritus. It doesn’t take much to make a tank with sand “detritus free” so I don’t like when certain people call it a “litter box”. To me that’s just ignorant. You don’t need to sacrifice aesthetics and go bare bottom (unless you like that look for some reason). Sand beds are beautiful and very easy to maintain.
