Sand is good.
I have had my main tank for 2 years with Super Naturals, it looks like reef sand, fine and dense, natural white, I don't remember the actual name. Everyone is impressed with the look of it. And it is easy to clean.
That said...the sand has chewed up several impellers (
HOB). But my Aqueon filter has been the best for that type of sand, lasted MUCH, longer, the other filters Walmart Aquaclear??, died in a month, and the whisper filter died 3 months.
It was suggested to put filter media around the intake to keep sand out of the filter, I tried that last week but it is ugly looking and is just collecting the debris on it which is unsightly too.
Just unplug the filter during cleaning and refilling, that helps keep out the sand from the filter. The other issue is air bubbler, I have a bar style which kicks up sand all around it, I wouldn't recommend that. lol
I am planning to add some medium stones around it, its in the back of my aquarium with a large rock in front of it, it kicks up a ton of sand.
It is dense and occasionally gets dark shadow look, maybe the gas pocket, I try to make a point to move it around a little so that doesn't happen.
On the other hand, I got a new kind a few months ago, from Petco and it is lighter with a slightly larger grain and doesn't seem to compact so much, it's in a different tank and it doesn't seem like it floats up as much but it is lighter and sometime actually floats on the water in little amounts, mostly when we are doing a water change.
I think they keep the gunk out of the bottom so it gets sucked up to the filter better.
Hope that helps.