Ok her it is I finaly found away to rid our tanks of black beard algea. For the last year I had a tank that got beard algea really bad, I done countless hours of research and learned just about everything there is to know about algea and treating it in FW tanks. At one point I went extreme and breaking the tank down and bleach washig everything plants, equipment, ect. This was the only way that was seid top be proven. Also ther mention of using hydrogenproxcide to kill it. Nothing worked with in a month is was back. SO there I was scratching my head again, all that work wasted. So a club member told me about seachem Florish excel. I knew that it help keep hair aglea in check but I been using it for a over a year and it never touched the bearded algea. So what next......... I called seachem 2 weeks ago and talked to them and explained it all to them... ( I like their products and use them) they said use the excel except heres the secret.......... You have to triple the dosage for you tank size. Guess what it works in 2 weeks of using it one a week any alge on plants is gone or dieing and the same for the dense fortest I had on my DW. I got so excited when I woke up today to see wood grain again, so i thought I pass this along.