I read that with coarse sand you tend to get a build up toxic gases that settle between the sand pebbles. Is this different for you?I don’t like super fine sand it tends to be messy. I use coarser sand.
The nasarius snails will keep the under sand area stirred up. They dissappear under the sand then you feed the fish and they come up from under the sand quite amusing to watch.. Other types of snails will get the glass and rock. The inverts are important. The problem lies in the fact that many are more delicate, like shrimp and urchins. They need a very clean and mature tank. They don’t do well in newer tanks. A mature tank would be over 1year and stable for at least 6 months. They need low nitrates. Another interesting invert when your tank is mature would be a fighting or tiger conch.