Carib Sea ACS05839 Super Natural Sunset Gold Sand for ...
Before I added the Marimo, I washed the sand for a good 20 or so minutes before the water ran clear. I put the sand I wanted to use into the tank (easy enough for me to do because of the small size of the tank, but the same concept would work just fine in a Homer bucket) and then ran cold water over it, using my hands to constantly move the sand.