I bought some Barley straw extract (with peat) for my aquarium in hopes it may help combat algae and release some tannins in the water collumn. It's designed for pond use but I thought I'd give it a try. The stuff is supposed to mitigate phosphates and nitrate buildup and even lower Ph somewhat. http://www.stillpondfarm.com/Microbelift_Concentrated_Barley_Straw_Extract_p/rmlcbse.htm The stuff is extremely concentrated. I added just 1/2 tsp into my 40 gallon aquarium, which is about the recommended dose. After a single use I notice no water discoleration (its supposed to tint the water somewhat), but my Rams bred a couple days later so it does not seem to stress the fish. Has anyone tried this product?