black diamond branded blasting sand, medium or rough grit is fine with corys
Many like Petco black sand I have read.
The blasting sand can have bits of iron in it that might stick to magnet cleaners and scratch glass.
Seems like a lot of work for just a color
I'd probably go with that Petco black sand before I'd spend countless hours removing iron with a magnet. Lol. The things we do for women right?
I recently switched to blasting sand. I ran a magnet through it, and didn't have anything stick. Maybe there could be super fine pieces or maybe I got lucky.
I guess it depends on the size of the tank too. Blasting sand is like $8 for a 50lb bag. If you need 100lbs you're talking $16 instead of $70-$100.
Many who want planted tanks go with Pool Filter Sand [ PFS ] on the cheap. It is more uniform and cleaner from the start then play sand or other choices. Basically vanilla color ?