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Small Pond Algae Control

Pond Algae Control Information for Small Ponds Less Than 50' x 50'

There's hundreds of types of pond algae.  The two most common are planktonic algae (looks like green pea soup) and string algae which looks like long green hair.

String algae is pretty simple.  It usually grows along the bottom or edges of your pond where there isn't a lot of water circulation.  To kill string algae you can use our Green Clean pond cleaner.  It works by oxidization and destroys the cell structure of algae cell walls. 

Plankton, our lovely "pea soup" algae is probably the most common type of algae in ponds and lakes.  It's the stuff that makes the water look green and causes you to not be able to see your wonderful fish.  The best way to explain how to get rid of planktonic algae is to first understand what causes it to grow.

Plankton requires primarily 2 things to grow: sunlight and nutrition.  The sunlight obviously comes from the sun and the nutrition comes from byproducts from fish waste, dead and decaying leaves, decomposed fish food (make sure you don't over feed your fish) decaying aquatic plants and weeds, and nearby chemicals and fertilizers that filter into the pond. (Particularly if your pond sits in a lower part of your yard).  Most ponds I've seen have at least some, if not all of the above nutrients in their pond. (And have green water, too!)  The way to get rid of or reduce the amount of algae in your pond is by reducing the amount of sunlight and nutrients available to it.

Sunlight can be reduced by providing shade to your pond either above or by adding aquatic plants such as water lilies or other floating plants including water hyacinths.  The leaves of these plants help to cover the surface area of your pond and also make the pond look pretty. You can also use an aquatic "sun blocker" or pond dye such as Aquashade.  Nutrients on the other hand, can be reduced in a couple of different ways.

To reduce the nutrients in your pond which is causing your algae to thrive, you first need to clean your pond.  Get rid of any dead and decaying leaves on the bottom or along the sides of the pond.  Once you have that done, get a skimmer so you can have leaves and debris that may blow into your pond get sucked up before they ever settle and start to decompose. If you don't want to get a skimmer, get a Pond Net (you also can keep out predators such as raccoons, blue herons, cats, etc. with a net) or make it a practice to clean the debris off the pond every day or so.

The next way to get rid of the nutrients in your pond is by adding beneficial bacteria to your pond. You see, there are 2 types of bacteria;  the "bad" kind of bacteria and the good kind!   Bad types of bacteria can cause a lot of problems to your fish's health and can be pretty involved to explain.  To keep it simple, these bad types of bacteria can eat away at their skin, their gills, and cause them to be sick and die.  Needless to say, you don't want the "bad" type of bacteria.  The good, or "beneficial" bacteria is a type of bacteria that is required to not only break down toxic ammonia from fish wastes into harmless nitrates (referred to as the Nitrogen Cycle - which is something you want in your pond) but they also consume the same nutrients as algae does!  So, when you add more beneficial bacteria, you starve out the algae, thus resulting in a clearer pond!  Beneficial bacteria also breaks down sludge build up, "muck" on the bottom of koi ponds and fish ponds and much more.  It is absolutely vital to having any healthy pond.  So what do you need to do to establish some beneficial bacteria in your pond?  Provide them a place to grow such as a biological filter, rocks, plants, and filter media.  Establishing a nice colony of beneficial bacteria can take 3-8 weeks but you can actually get a "jump start" on things by adding some beneficial bacteria to you pond like Microbe Lift.   It works great (we use it on our own small ponds and water gardens) and it can be used throughout the season as a good maintenance plan to keep your pond clear.   We also recommend our PlanktoniX Pond Bacteria beneficial for large fish ponds over 50' x 50' in size all the way up to lakes several acres in size!

I do have to mention some other products that are out on the market (and yes, even on our website) that will "destroy" algae, but these products will only work for a short time.  They are a temporary solution.  They work by killing the algae and then the dead algae is supposed to be filtered through your filter.  What essentially happens is that the dead algae builds up on the bottom of the pond and creates an organic "compost pile".   This provides tons of nutrients and causes more algae to bloom in a couple of weeks.  People who continually use these products are actually making the algae situation worse.  You're continually providing more and more food the very algae that you're trying to get rid of!  It creates a vicious cycle and you need to stop the cycle.  By continually adding these chemicals & algaecides to your pond, you're changing the pond's chemistry and ecological system.  You need to add beneficial bacteria to the pond to reduce the nutrients available to the algae.  This will eventually starve out the algae and stop the cycle and result in a clearer, healthier pond.