Join Date: Nov 2012
Location: Where the devil went down to!
Coal slag is safe for kuhli's and corys. as i have both and they seem fine. black diamond is environmentally safe, check out their website it will give a good explanation of what it is.. My loaches still burrow in the substrate and i don't notice any cuts or abrasion of any sort.
I am very pleased with Black diamond blasting sand. and I plan on using it as a cap for my first dirt tank.