On the lower part of our property is a spring-fed pond that is occasionally used to irrigate surrounding crops. It's a bit barren, and long term I'd love to introduce some ornamental grass and other landscape elements to make it a bit more pleasing. But the problem of the moment is the slow and steady growth of filamentous algae all around the perimeter of the pond. The algae is particularly thick at the upper end where the spring is located. From what I've read, the problem is likely a result of runoff from fields and a septic drain field that lies a couple hundred feet above the pond.

I had heard of barley straw as a solution to controlling algae, but after further reading I found that the results were inconsistent, and even when effective the straw needs to be introduced early in spring, before algae growth occurs. I wrote to the Penn State cooperative extension – an excellent resource for any agricultural-related questions – asking for their advice on managing the algae. I specifically wanted something non-toxic that would not harm the numerous fish (including two huge carp) that call the pond home. They pointed me in the direction of a product called Green Clean.

I'm guessing the pond is about 1/3 of an acre in size. My measuring method is admittedly suspect, since I used Yahoo Maps to view an aerial photo and gauge the relative size of the pond. I've been meaning to do some real measurements and somehow I just never got around to it. At any rate, based on the size, I'm estimating volume of the pond is 350,000 gallons using an average depth of 3 feet. 4 pounds of Green Clean should do the trick, but I'll be doing more thorough measurements this weekend to make sure that's correct.