jckkc
New Member
I received a 45 gallon reef tank from a friend who was moving about a month ago. It is my first reef, I only had pure fish tanks before. On the glass I noticed many small critters about the size of fine sand on the tank walls slowly moving around about a week after getting it. Now, three weeks later they are about the size of a large grain of sand and number about 100. Does anyone think they are dangerous. My friend swears he as never seen them nor did he add anything different in the water. The urchin, anemone, 2 clowns and assorted snails and crabs are doing fine. Any ideas? 
