Hey Fishfoum, I recently purchased super natural moonlight sand from Caribbean Sea (x2 20lbs x1 5lbs) and I have a small problem. When I picked up the two 20lbs bags they had algae in them with a slight brown colour, just the 20lbs, not the 5lbs bag. The small bag had perfect white colour with no algae and after washing the 20lbs pound the sand has turned kind of grey. Should I return them or is there anyway to fix the colouration? Will my filter clean the sand? Please let me know if I’m missing something.