Wanting to use the black diamond sand but not sure due to the hearing that medication for fish (if it was necessary)would cause some sort of chemical reaction. Got a 210 tank im settings up so trying not to spend a fortune on substrate. Any one have any experience with medicating tanks with this sand? Also im going to have my silver arowana, silver dollar shoal, payara, and a few plecos(for now)anyone know of any issues with that substrate and those fish? Thanks for the input guys.