Shango, Have you tried H2O2? I tried this in my shrimp tank after they had all passed away. I had some plants in there that I wanted to save but they had developed some clado on them. So I gave the peroxide method a whirl. Amazingly it worked very well! The only thing that I noticed as a "negative side effect" was that the roots of the duck weed all fell off. For me it was a good thing because I didn't want that stuff in there anyway :) Fine leaved things in that tank were also affected but recovered. The basic formula I found was 1oz / 10 gallons. Be forewarned however, I don't know what it does to live stock. Snails seemed to survive fine and I've read that fish aren't bothered by it but I cant say from my experience/experiment. The best part of H2O2 is that once it's done reacting it turns into water and oxygen so you don't even have to do a water change :) Aside from the chemical used, spot treatment usually works very well. I've found if you are vigilant then you can eliminate almost all of the algae with this method. Then if you can figure out what the imbalance in your tank is you can correct it and the little algae that is left will go away. Also, if you do a heavy spot treatment and get almost all of it, overdosing excel does a good job of getting rid of the rest I've found. -Bryan _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member