Buy the "Plankton Culture Manual" by Frank Hoff and Terry Snell. It's available from Aquatic Ecosystems and other large outlets. It has an entire chapter on daphnia culture. Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9. Archives are at http://fins.actwin.com/killietalk/ Modify your subscription at http://www.actwin.com/mailman/listinfo.cgi/killietalk