The company that has begun testing for the various strains of, & population size of bacteria in reef aquariums tested [if I remember corectly?) a new system of W.W.Cs, and found that just using the water from an existing tank is enough to kick start a new system because of the bacteria in the water column. Interesting stuff. I wish I could remember where I found this article; I would link it for you.Only 10g to help start a friend out in the hobby. Moving over about a 3 lb rock plus 5 marinepure spheres from a 75g tank. Everything was moved over this morning with half the new tank full of chaeto expecting pods to start seeding as well. Hoping to leave this running for a week before testing with some CUCs before a single fish. Ghost feeding as well.