The-Wolf
Ex-LFS manager/ keeper of over 30 danio species
You might want to just clarify the "silver sand" bit. There are two grades sold (at least here in the UK), known as 'sharp' and 'smooth'. Sharp sand is unsuitable.
You are quite correct in saying that sharp sand is unsuitable
but every bag of sharp sand I've ever seen is labled as such and
every bag of silver sand is either labled 'silver sand' or 'play sand'.