Pond Management: Sometimes You Fail! Keep the Faith!

Friends….. Sometimes our best efforts lead to results that are less than favorable…. There are times when even the professionals screw the pooch and have to admit that they have failed. These lessons are important for all pond owners.  Big ponds, watergardens, lakeshore properties….. All waterbodies can lull us into a false sense of security, be wary fellow limnological enthusiasts, as the environment can often throw curveballs that are unforeseen.

I am no exception to this.  Mother Nature is a fickle mistress, she giveth…. and she taketh away (and boy, when she wants to taketh, she can taketh very aggressively).  These unfortunate occurrences usually rear their ugly heads when conditions rapidly change, when you miss a key characteristic of the resource (physical, chemical, cultural, or environmental), or when you don’t notice a subtle change in the environment that has been building up for a while.

Allow me to take you on a trip through some of my tribulations so you may learn to be better managers for your particular water bodies.

1) Rapid condition change:

There once was a municipality that contracted me to manage their community swim pond.  Beautiful place: clear water, good circulation, and a good balance of fish….. Usually this system was a breeze to manage.  Swing by once in a while, add some bacteria and enzymes to help out the micro-biota, maybe some phosphorus reducing agent if I felt the need…… no problem.  Welp, then something strange happened.  Mere minutes after I left the property, the wind died and the ambient temperature rose 10 degrees to about 90-95 degrees F. The enzymes that I added are catalysts for rapid respiration in any aquatic system. Normally this is good…. nutrients get chewed up by the microbiotic community and all’s well…. This time however, the rapid rise in temperature resulted in a drastic reduction in the pond’s ability to hold oxygen.  So, my treatment with 100 natural additives proceeded to suck all the oxygen out of the water column, killing the vast majority of fish in the pond.  As you may be able to determine, the park manager was a bit shocked to see all the dead fish and had to send all of his lifeguards around with nets clearing up the mess, as no one from the community wanted to swim in a pond with a bunch of dead fish (weird…right?).

This problem is impossible to anticipate, but it teaches us to be uber vigilant when gauging conditions before we initiate any management action.

2) Overlook a key characteristic of the resource:

There once was a customer who wanted a backyard pond installed.  It was beautiful! They lived on a ridge overlooking field and forest…just serene.  Welp, it turns out that after everything was installed, the pond water was green……and I mean REALLY GREEN.  I had no idea what was wrong.  This pond was constructed with a liner and a custom designed filtering system over and above what should have been necessary to keep the pond clean.  Then I tested the source water. (This is Joe’s shame face.)  The landowner’s well water was contaminated with agricultural runoff. The Nitrate levels were 10 times the average levels (for groundwater in that area), which led to runaway algae growth.

The lesson here is: ALWAYS know the conditions at your site.  If I would have tested the water beforehand, I would have seen that I need to incorporate a Goliath of a filter bog/system to mitigate the excess nutrient issues present in the source water.

3) Condo Pond Issues:

So, there once was a condo that had a nice pond for the residents to enjoy.  Good fish, pretty fountain, jovial pond manager who swung by every so often to see how things were going.  Welp, over the course of several seasons, the pond began to degrade.  The water clouded up, and new weeds and algae started to slowly become an issue.  This intrepid water resource manager wrote it off to natural aging and just went on his way.  Well, unbeknownst to the pond manager, the residents of the condos let some goldfish go into the pond.  Furthermore, another resident started dumping the remains of their supper and potting soil from their potted plants into the pond.  The combinations of these two things wrecked this pond.  The goldfish multiplied and dug up the bottom sediments, turning the pond an ugly mud color.  The slow addition of nutrients and soil caused a slow increase in nutrient issues that then led to nuisance weed and algae issues.

The moral of this story is CONSTANT VIGILANCE! Tiny changes can have LARGE impacts over time in any aquatic system.  To this day, this condo pond is not back to the state it was in before the problem started, and it will be a long, expensive trip back if the community wants to spend the resources to rectify the issues.

This same pond has had an influx of exotic Apple Snails (probably from aquariums).  These critters are actually helping the pond as they are filtering out a lot nutrients and sediment.  Alas, they are an invasive species and will most likely spread to other waterbodies unless they are removed from the system.

Every pond (large or small) can be affected by these oversights.  Backyard watergardens/koi ponds are especially susceptible to change due to their small size/water volume.  So, beware!  Learn from my misfortunes and please ask questions in the comments if you are noticing change in your pond.  Change is not good (normally) in an aquatic system.  We’re looking for balance and stability in the watery world that we oversee.

Thanks for reading,

JOE CADIEUX
Senior Biologist
Midwestponds.com

📷: 

https://vineyardgazette.com/news/2008/08/28/great-pond-algae-bloom-cause-serious-study | http://www.blacklagoon.us/