The Accidental Science Project

 Wayne and I spent the heat of the summer fixing up an old gazebo that we probably won't spend a lot of time in now that the fall  is upon us. As part of that restoration we installed a fish pond which promptly turned a murky dark green- how charming. I had never considered that area to be sunny as there is a Bradford Pear tree not five feet from the pond with branches that reach over the gazebo. The stubborn rise in algae proved that I should have planted sun loving Bee Balm there instead of Cinnamon Fern.

 "The Accidental Farmer Cafe" is a business in South Hero VT, whose name I am fond of as it rings truth in how many of my pastimes came to be. My mother being allergic to fur bearing animals presented me with my first pet around the age on nine. While I dreamt of a German Shepard or perhaps a Mustang, I embraced my new goldfish companion.  My goldfish bowl eventually lead to a ten then twenty gallon aquarium. At one point we had two twenty gallon tanks then a fifty, a tiny fish pond and finally (I say with some certainty), a fifty gallon fish pond in the summer with the 50 gallon aquarium being their winter home. My tank is in the dark basement for the same reasons that I should have found a more suitable spot for my pond. 

Wayne "wondered" out loud and in my direction, if we had any fish at all left in the pond as he could no longer see them. He suggested that I add second fountain pump but with a filter, so I relocated the one from our original (now fishless) pond out front. When this failed to clear things up, I tossed a Plecostomus  (an algae eating fish) into the mix. Wayne also informed me that the problem was too much food and so I cut back on that. Eventually I resorted to partial water change every three days and added a pond algicide. Imagine my surprise this week when I not only discovered that I still had fish, but also a frog! To recap; this pond is 50 gallons, has nine fish that are fed, no plants, is in direct sunlight part of the day and has two pumps one of which has a filter.

Not to be outdone, our 15 to 20 gallon pond out front acquired a rather portly toad who happily takes a dip in its crystal clear water; but mostly it just sits in the spot that the duck fountain splashes the water over the edge. To recap: the clear pond has no fish, no fish food, no plants, no direct sunlight, a super cute toad and a non filtering duck fountain.

A curiosity took over me and soon I was making pit stops in the usual places for an unusual reason. I tend to file conversations in the back of my head like a camera stores photographs in the cloud. This accidental science project (I use science loosely here) opened my conversation files and out came Ian Deyo who wanted to learn more about the thick mats of gunk that float to the surface of Lily pond around the end of July. Ian stated that he couldn't remember there being a problem with them while growing up. I believe that the mats are algae and my best guess is Philamentous; but given there are 30,000 species of algae, some of which are toxic, it would be best to send a sample to a lab. Wayne and I walked to the pond a couple of Saturdays ago to get a closer look at the algae, only to discover that our moderate drought had separated us from the pond water by a stretch of bad smelling mud, goose prints and decaying lily pads.

I thought that it would be best to redirect our efforts again to a more controlled environment. With chlorine and fresh water no longer being added, the filters no longer operating and the children dispersed back into the community, I thought for sure that the town pool would no longer be its usual pristine self. What we found there however, tempted me to scale the fence to take a dip. So I flagged Seth Deyo down to answer a few questions. Seth confirmed that the pool was closed and when it was open they used chlorine that  maintains the pool's ph around 7.4. He suggested that I go back to check things out as they had drained the water down and things were starting to get green. To recap: When filled and operating the pool is clear. Shortly after turning things off the pool is clear, one week later without operating systems and with significantly less water in the pool it is green with algae. Direct sunlight all day, no fish, no plants, no added nutrients, temperatures had dropped into the 50's at night and the 70's during the day. 

I was seriously beginning to think that there was no rhyme or reason for why some bodies of water turn green while others don't! I wanted to give it one last observation before tossing in the towel and that involved actually getting into the petri dish if you will. I had been trying to visit the Vernon Dam fish ladder all spring and summer but found it closed each attempt. So this weekend we took a trip up to the Bellows Falls fish ladder. There we were greeted by the Nature Museum Environmental Education Intern Tristan Hayes. After a thorough introduction to what awaited us, we entered the exhibit. Wayne of course thoughtfully viewed it all while I bolted down the stairs to the observation area in search of green.

Before racing back to have another chat with Tristan, I followed Waynes' example and stopped to read a chart titled, "Benthic Macroinvertebrates as Water Quality Indicators" I mention this because a wide variety and high number of these aquatic animals and insects (without backbones), points to good water quality; and yet clearly several kinds of algae were present. Also, it seemed that some of these creatures were feeding on the algae. Tristan added to this information, explaining that when the fish ladder opened to the public in the spring during a long cool period, the glass was clear. Then on July 4th with  unseasonably high temperatures, the fish migration seemed to stall and the glass became heavily covered with algae. Recap: Swiftly moving, uncontained and aerated river water when cool was associated with fish migration and little algae growth. A prolonged period of high air temperature was associated with algae, Macroninvertebrates indicates good water quality, September presented with diminishing algae in both brown and green colors and a variety of algae types. 

While I know that it seems that we are no closer to solving our mystery, I will have to take up the trail in my next installment. Until then, If it is in the water, has an odor and / or  is blue-green, keep yourself and your pets away.- Norma Manning

Small Farm Pond at the South End of Pond Road

Planktonic Algae -Penn State

How to Identify Different Algae Types -SePro Corporation

What is Algae? -Department of Environmental Conservation