Algae Destroyer is different. That contains Simazine, a different chemical. People also use copper compounds for killing algae, and there is some use of hydrogen peroxide for some species. I've heard a lot of people complaining about green water lately. I think Kate had some good comments there. Dealing with these algae blooms often requires a lot of experimenting to limit the "causes." Also once it is established it tends to recycle itself. That is, cells that die nurish new cells. Something that might be worth a try would be Sandu's technique of putting in a bunch of Water Sprite to use up nutrients and block light. Steev Trish wrote: > When I had green water, I tried Algea Destroyer...it > didn't do anything.... ------------------ To unsubscribe from this list, please send mail to majordomo@thekrib.com with "Unsubscribe gsas-member" in the body of the message. Archives of this list can be found at http://lists.thekrib.com/gsas-member/