I think your gona need a bigger CUC. is my answer. Too many tanks are deficient or badly stocked, with the wrong sort, because they don't know either what it eats, how, how often, and if they're compatible with each other. And the tank owner don't keep up with whats going on with his inverts population. i have some dust thats unavoidable, waterflow will send sands and debris from what ever is happening in the tank. But if you have food accumulation that causes, nitrate problem, its a lack in a proper CUC.
One in particular is the brittle star or and serpent star. Both are basically stomachs on foot. Each disc contains 6 stomach pouch, and when they eat they kina go dormant for a bit. One reason you don't see them often. In my 150G i have 12 serpent and brittle stars. None will eat at the same time, or on the same nights. But i'll have at least one moving and working daytime or night time for sure while the others are resting or digesting. They don't have much to feed so after eatinga bit they can be quite a while without eating. So you can stack those up for detritus eating specially if you want to see them moving. I'm actually going for the number 20 in my tank. One advantage of these guys is that they do rocks, not only sand like most snails.
And i have no hermith because they eat snails, it doesn't matter how cute they are all crabs and hermiths are *****. And you'll have to buy new snails every 2-3 months or so.If you really want hermith get the smallest and don't put any bigger shells they'll die small but at least they wont take your snails with them.
Urchins eat the most variety of algeas more than any snails combine. one per 50G is enoughor they'll starve to death.
Conch is the best snail bar none for algaes and again one per 50 gallon or it'll also starve, churns your sand really good too.
Babylonia zeylanica ,areolata the big babylobian snails are the best detritus eating machines and live for ever. some say its attacks, if you were starving you'd eat anything too, they need to be fed enough i only have 15 in my 150 G so 1 per 10 G is enough. And you have to feed it. Or yes it may attack others.
Nassarius are also good and no relation to babylonians like some say, totally different genus.
Stay away from sand sifting starfish it basically eats every microbes in your sandbed leaving it sterile and it can no longer help in the biochemical clean up of your tank period. And sooner than later it will starve too.
Fromia starfish and the like are the best since they eat algaes and microalgaes before they become a problem and some microfauna.
Turbosnails are very good too but night crawlers.
Some snails live at 69oF and to put the at 77oF+ wil kill them slowly by cooking them and they'll die.
Your best friend in a tank is a cucumber, tigertails are the safest IMO .They digest left over poop into its basic elements and return the sand completely cleaned up and areate your sand too.
Cerith snails but i do without i do my own glass.
