National Geographic Black Sand- Reef Safe???


New member
hey folks

Im just getting back into the swing of things with owning a reef tank. when setting up my 20L I saw petsmart had this very fine black sand made by national geographic (petsmart brand).. I really liked the particle size and texture so I decided to give it a shot

the tank has been up and running for 3 months now, I have gone through the stages of algae ( diatoms, hair algea, cyano) and everything is looking healthy LPS is doing amazing, Inverts no problem, however I am struggling to keep SPS.. they always seem to bleach & or RTN/STN :headwally: my levels are in check and im starting to fear perhaps the sand may not be reef safe... any ideas? before I begin siphoning it out I would like some input

I should add that I have attempted to call petsmart several times and well... enough said they don't know much about saltwater

A sea K

New member
If it does not say it and you dont know for certain then I would ditch and get an aragonite based sand. It acts as a buffer and does not have silicates. I have seen aragonite in black so you can still keep the color you prefer.