Little white bug like creatures

Just fired up the lights in my isolation tank - planning on a new fish purchase. Noticed a ton of little white bug like creatures crawling on the back of the tank. They are very small and have legs. As soon as I turned the lights on they started evacuating the back of the tank and into the water. I have some macro algae and a couple of pieces of live rock in the tank. Haven't been able to find them in the nuicance critters section. Anyone have a swag as to what they might be?

PS - so small can't get a pic.

 

Isopod, copepod, amphipod or all of the above

 

Good for your tank. They are food and do some work as part of the clean up crew.

 

Yup, Pods probably, good stuff!

 

Our tank turns 3 weeks old tomorrow and our glass is getting covered with these guys too...we've also been told not to worry...pods are good.