Davy, Check out the following URL- http://ohioline.osu.edu/hyg-fact/2000/2070.html Your mystery creatures are almost certainly springtails. I have had them before in my tanks intermittently- they are harmless. Cheers, Cory ------------------------------- Cory and Susanne Williamson 7800 Thompson Drive Prince George, BC V2N 5N5 E-mail: cswilliamson at telus_net Phone: 250-964-3973