Pond FAQs - Algae

Answers to common questions related to Ponds

Design  ·  Materials  ·  Fish  ·  Plants  ·  Algae Control

    Algae Control

Troubleshooting Algae
Types of Algae
Balancing Algae
The Yearly Cycle of the Average Pond

Algae Control Methods

Algaecides
Plants
Physical removal
Don't overfeed fish
Fix Leaks
Control Run-off
Remove Debris
Clean your BioFalls^® and pond completely, once a year
Relax

Questions to be asked to determine possible causes & solutions to Algae

What type and what size of filter is on the pond?
Has bacteria been added? If yes; How much, How often, and Liquid or Dry?
Has the skimmer net been cleaned/emptied?
Has lava rock been put into the media nets in the BioFalls^®?
Have the BioFalls^® mats been cleaned?
Are there rocks and gravel in the pond?
Is any run-off being directed in the pond?
Is there a leak in the pond?
How many plants are in the pond? What type?
Has string algae in the pond been physically removed? How?
Has dead fish or other dead organic matter been left in the pond?
What type of location is the pond in?
Has a water change been done on the pond? Full or partial?

<> Troubleshooting Algae

Your pond is a natural ecosystem that supports plants, fish, frogs, tadpoles, microorganisms, dragonflies, birds and other wildlife. Algae, just like the rest of your ecosystem, is part of nature. Algae are beneficial. They help remove fish wastes and toxins from the water. Some types of algae will actually help the clarity of the water. The key to maintaining your pond is not to try and eliminate algae, but to keep the algae in balance.

<> Types of Algae

There are hundreds of types of algae throughout the world. However, the two types of algae that most water gardeners experience are suspended algae and filamentous (string) algae.

Suspended algae consist of millions of microscopic algae floating throughout the water. This causes the water to turn green or "pea soup" color.

Filamentous algae or string algae form long and short hair-like strands. It attaches itself to rocks, gravel, plants, or any surface area it can find in the pond. Both forms can be reduced by properly balancing your pond.

<> Balancing Algae

Algae, single-cell plants, require nutrients and light to survive. Reducing algae's required nutrients will result in fewer algae. How do you reduce algae's nutrients? It's simple, follow the recipe for a well-balanced pond. A well-balanced pond includes the following. BioFalls
Supports large colonies of bacteria and enzymes. The bacteria and enzymes use up nutrients and help break down fish waste (nutrients) and organic debris (nutrients).

Skimmer
The skimmer removes and collects leaves (nutrients) from the top of the pond.

Rocks & gravel
Provides surface area for bacteria to colonize, turning your entire pond into a biological filter that will break down fish waste (nutrients) and organic debris (nutrients).

Plants
Plants have the same nutrient requirements as algae. They directly compete with algae for nutrients and light.

Fish
Larger Koi (greater than 10 inches) will eat a tremendous amount of string algae.

Bacteria
Using bacteria in your pond to boost Mother Nature's ability to balance your pond.

<> The Yearly Cycle of the Average Pond

Most ponds will have a similar algae pattern throughout the year. Do not be discouraged in spring if your pond turns pea soup green, or you have string algae problems. Be patient while your pond wakes up from it's winter slumber. The pond will need to balance itself out. During the spring, there is an abundance of nutrients in the pond. Algae are the first to take advantage of these nutrients. Algae will be reduced as the bacteria and plants re-establish themselves and start using up their share of the nutrients. Some ponds take longer than others, but your pond will once again be crystal clear and string algae will diminish noticeably as the season progresses.

Algae Control Methods

<> Algaecides

NEVER USE ALGAECIDES IN YOUR POND!!!

Algaecides are only a temporary cure for the problem. The algae is killed off, sink to the bottom and begin to decompose. The decomposing algae release all of the nutrients that it had taken up, creating a nutrient rich environment for the next wave of algae. The next wave of algae, about a week later, will be larger than original, due to all the nutrients available. Using algaecides will cause your pond to become "chemically dependent", which is not good.

<> Plants

Plants are probably the most important addition to your pond, since they directly compete with algae for nutrients and light. Add a variety of plants to your pond. This not only creates a natural look, but also will help reduce the algae in different areas of your pond.

Place water hyacinth and water lettuce in your BioFalls^®. These floating plants reproduce rapidly, using enormous amounts of nutrients. Remove the older floaters when they start to over-run your BioFalls^®. The discarded floaters make great nutrient rich compost for your garden.

Plenty of bog and marginal plants should be added to the pond. Plants such as cattails and iris use large quantities of nutrients. They are hardy and will be back each spring to help you balance your pond.

Cover the surface of the pond by planting lilies. Lily pads float on the top of the pond soaking up the warm sunlight. The lily pads will reduce algae by preventing sunlight from reaching the deeper portions of the pond.

Don't overlook oxygenators! They soak up nutrients and sunlight directly through their leaves. Think of them as nutrient sponges.

<> Physical removal

Physically remove clumps of string algae if it begins to overtake the pond. Cut away the algae where it is attached. Think of it as "weeding the pond".

<> Don't overfeed your Fish

Fish food that is not eaten by fish will decompose in the pond and increase nutrient levels. Only feed the fish amounts that they consume within a few minutes.

<> Fix Leaks

Tap water can have an abundant amount of nutrients in it. Continually adding large quantities of tap water to compensate for a leak can promote algae growth. Fix water leaks when they are discovered.

<> Control Run-off

Never use lawn fertilizer or insecticides on trees around your pond or on areas of your property that will drain towards your pond. Lawn fertilizer and insecticides will cause large nutrient blooms and will severely threaten the aquatic life inside your pond.

<> Remove Debris

Keep your pond free of debris. Don't let the skimmer debris net over-fill with leaves. Decaying leaves and seeds in the skimmer and pond will contribute to unwanted nutrients.

<> Clean your BioFalls^® and pond completely, once a year

Start off each spring with fresh water and a clean filter. Do not clean your BioFalls^® more than once a year unless excessive run-off clogs your mats. Cleaning your filter mats with tap water will kill your bacteria.

<> Relax

Your pond is not a hot tub! Ponds that have no string algae are unhealthy and sterile. As your water warms and bacteria and plant colonies grow, your algae levels will be reduced.

Keep in mind, algae is a natural part of the ponds ecosystem! It will never be eliminated, but can be kept in balance.

Ponds that have recently been installed (under 4 weeks) can have a higher occurrence of planktonic algae (pea-green water). Be patient!! The bacteria takes time to seed itself. This algae will go away after a short period of time, usually a few days to a couple of weeks from the first time it is noticed.

Technical Questions & Answers

The following section on algae is a step-by-step list of questions the Technical Department at Aquascape uses, to determine the possible cause and solution to common Algae problems.

<> What type and what size of filter is on the pond?

If a BioFalls^® and a skimmer are installed in a pond that is larger than the maximum capacity of the filtration system the pond will not be filtered properly. Also, if there is a heavy fish load in the pond, the filter system may not be adequate.

<> Has bacteria been added? If yes; How much, How often, and Liquid or Dry?

The bacteria should be added according to the recommended dosages.

Dry bacteria should be added at a rate of one teaspoon for every 1,000 gallons.

Liquid bacteria should be added at a rate of one ounce for every 1,000 gallons.

Bacteria should be applied daily for the first two weeks when establishing your pond. Re-apply the same dose once every 10-14 days after the bacteria is established. On average, your pond needs more bacteria spiking when the water is cold and less when it's warm.

<> Has the skimmer net been cleaned/emptied?

If you do not empty the skimmer net, excessive amounts of organic material (leaves, fish food, algae, etc.) will build up in the skimmer. This organic matter will eventually decompose and add nutrients to feed the algae in your pond.

<> Has lava rock been put into the media nets in the BioFalls^®?

The media nets supplied with the BioFalls^®? should be filled with approximately 25 pounds of lava rock. Lava rock contains millions of spaces of surface area for bacteria to seed and grow.

<> Have the BioFalls^® mats been cleaned?

The BioFalls^® mats and media nets filled with lava rocks should be cleaned only once a year. This is usually done during the spring clean-out. Rinsing off the BioFalls^® mats will kill bacteria that has seeded itself throughout the mat. The water from city-supplied tap contains many chemicals that are used to treat drinking water, such as chlorine, that can kill-off the beneficial bacteria.

<> Are there rocks and gravel in the pond?

Rocks and gravel in the pond, besides protecting the liner, act as surface area for the bacteria to grow on.

<> Is any run-off being directed in the pond?

Rainwater and other types of run-off being directed into the pond can add an excessive amount of nutrients. Fertilizer in run-off from a lawn can also cause excessive amounts of algae to occur in the pond, mainly because algae is a plant and fertilizer is a type of plant food. Try to prevent any run-off from entering the pond.

<> Is there a leak in the pond?

A leak in the pond will cause you to add large amounts of water to the pond on a regular basis. This water can contain excessive amounts of algae-causing nutrients, such as phosphates and nitrates. City tap water may also contain chemicals, such as chlorine, that will harm the eco-system. Before trying to correct the algae problem, fix the leak!

<> How many plants are in the pond? What type?

Algae is a type of plant and will flourish if it has plenty of nutrients to feed on. Putting water plants in your pond will help to remove nutrients that would normally be eaten by algae. These plants will directly compete with algae to remove nutrients.

<> Has string algae in the pond been physically removed? How?

Do not rip the string algae out of the pond. Ripping the string algae out of a pond will cause hundreds of small fragments to break off and attach elsewhere in the pond.

Use scissors and hold the algae when you cut it. This will make sure that you remove virtually all of the filaments that you cut off.

<> Has dead fish or other dead organic matter been left in the pond?

Dead organic matter left in the pond will decompose and produce excessive amounts of nutrients.

<> What type of location is the pond in?

Algae is a type of plant. Like most plants, it will grow better in sunny locations. Ponds can be built in any type of location, sunny or shady. Sunnier locations may have a slight increase in the amount of algae and require a bit more maintenance to balance the pond. Shady or wooded locations may increase the amount of times the skimmer net needs to be cleaned during the fall when the trees are losing their leaves. By no means should either of these situations deter you from building a pond there.

<> Has a water change been done on the pond? Full or partial?

Performing a full water change in the pond is one of the final things to consider when trying to control algae. Be careful, ordinary tape water can contain high levels of nutrients, such as nitrates and phosphates, which algae thrive on. If you make a complete water change, you may be adding nutrients to the pond rather than reducing them. We usually reserve water changes as a last resort.