Ponds are a necessity for every fish farmer that intends to cultivate fish. However, pond turning green is aproblem every fish farmer, whether novice or experienced, has gone through at least once in their fish rearing experience.
Ponds turn green when algae float on the pond, or there is an imbalance in the nutrient in the pond water. When there are extreme levels of nitrate phosphate in the water, it will cause the algae to grow even more.
Knowing this, fish farmers who wish to control the growth of the algae in their pond can use ultraviolet clarifiers(UVC) in conjunction with a good filter. Owners of fish ponds can also use algae-eating fishes to control algae growth in their ponds.
This article will give detailed information on pond turning green– causes and what to do.
Causes Of Ponds Turning Green
It is unsightly when you see your clear pond start getting murky and green. Although this may not have any adverse effects on your fish immediately, algae can start to compete for oxygen with your fishes if left uncontrolled. Below are some reasons why the pond water turns green;
Algae-Boom
Algae grow in a pond when there are nutrient imbalances in the pond water. As algae, fish waste, and grass decompose, it will release some nutrients into the pond, which will cause the algae to grow.
Too much sunlight and excess nutrients can lead to issues with floating algae in the pond. These extra nutrients are usually caused by feeding your fish too much, a lack of proper pond filtration, stormwater run-off.
You can invest in some quality filtration systems for your ponds. Here are some excellent picks below;
- Pondo KOI Pressure Bio-Filter
- Jebao CF-10 Bio-Filter
- Jebao Cw-55 Pond and Aquarium Clarifier
- Sun CPF BIO PRESSURE FILTER
- Jebao NPU Clarifier
- Pondmaster DNR02910 2910
- Sting Ray 1200
Non-Growth Of Oxygen-Producing Plants
Oxygen availability is an essential part of the pond water staying clean. Fish farmers should not be quick to remove any plant that grows in their pond as some of these plants produce vital oxygen that can keep the water clean.
Some good oxygenating plants for ponds are;
- Eel Grass
- Arrow Head
- Hornwort
- Red Rotala
- Water Sprite
- Water Wisteria
- Coon Tail
Low Ch Value
The value of carbon in the pond is an integral aspect of the overall pond environment. Carbon is formed in water when free Carbon binds with magnesium or calcium. When this happens, it creates a CO2 source for plants and algae. One way to stop stagnation and stop Pond turning green is to increase the CH value.
High Ph-Value
The average PH value for pond water is above 7. A PH value that is too high is due to poor pond management.
A cause of a high PH value can be from biogenic decalcification happening in the water, which will result in excess algal growth, and then the pond will turn green.
High PH means that the pond water\’s Alkalinity is rising, which is often caused by water flowing into the pond from other sources. Pond owners should always use a PH tester to check the Ph value of their ponds. PH fluctuations should not be more than 0.8 per day.
Pollution
Ponds will get polluted through the constant use of chemicals on the pond. Also, pond owners should ensure that their ponds are away from people who want to throw waste into the pond. When ponds are polluted, it is easy for algae to grow and turn water green.
There are significant causes of pollution that every fish farmer must avoid. Some of them are;
- Dumping refuse in ponds
- Too much use of Chemicals
- Pesticides
- Fertilizers
- Air Contaminants
Light Exposure
Filamentous algae will grow around shallow parts of ponds because this is where they have the most access to sunlight. When your pond is open to the sun directly, it will encourage algae growth resulting in water becoming green.
Algae enjoy sunlight and will thrive when exposed to it. Deeper ponds may not have a problem with sunlight, but shallow ponds will. Fish, when exposed to the sun, can also get skin burns
Pond owners should reduce the amount of sunlight that comes directly into their ponds.
Temperature/Turbidity
Tiny particles such as clay and sediment from the bottom of ponds can move naturally when fish feed in the pond. The dislodgement of these particles will result in low turbidity of the water.
Turbidity will affect how much light gets to the water and ultimately affect the pond\’s temperature. When the water is more turbid, the water will get warm, encouraging the growth of green algae.
What To Do When Pond Water Turns Green
When pond water starts to turn green, it could be due to various factors. Usually, algae are the number one culprit in cases like that. Pond owners should be aware of measures to solve the problem, such as algae-eating fish, Clarifiers, Sufficient aeration, etc.
The following paragraph will elaborate on several things to do when your pond water starts turning green.
Use Of Algae Skimmer
This method is speedy for clearing accumulated algae in the pond. Although it is more of a temporary measure, it provides immediate relief. Drag a pool skimmer across the surface of the water, and the algae will come off.
A pond skimmer will remove floating debris on the pond water before it has the chance to sink to the pond floor. The skimmer will also hide and cover the pond plumbing from view, which will make your pond cleaner and well arranged.
Some good pond skimmers you can invest in are;
- GKan Moore Pool Skimmer.
- Anothera Upgraded Pool Skimmer.
- Aquascape 43020 Series
- Tetra Pond in Pond skimmer
- Miya Pool Net.
- Jebao SK-30 Floating Pond Skimmer 660 GPH
- Sepetrel Pool Skimmer
Planting
Sago pondweeds will remove excess ammonia in the pond water. It is essential to plant floating plants like water lilies on your pond because they will block the extra sunlight that can encourage algae growth.
These plants will absorb nutrients in the water that the fish releases and will reduce the availability of the nutrients. When this happens, it will slow down the algae growth.
Some plants pond owners can use on their ponds include;
- Water lilies
- Coon Tail
- Water lettuce
- Water Hyacinth
- Cardinal Flower
- Marigold
- Blue Flag
- Duckweed
Use Of Aeration System
Aerators are one of the best solutions to use to stop the growth of algae in ponds. Adding an aerator to your pond will control the development of new algae that turn the water green.
Aerators will also enhance the habitats of ponds, improve the quality of the pond water, reduce algae, remove phosphorus, break down unwanted bacteria, reduce mosquitoes, and remove foul smells.
Aerators that fish farmers can consider;
- HQUA Pond and Lake Aerators
- Aquascape 75000 Pond Air 2
- HQUA PAS10 Pond and Lake Aerators
- HQUA SWA20 Sceptic Aerator
- Tetra Pond Air Pump
- Aquascape Pro Air
- The Pond Guy Pond Aerator
Phosphate Reduction
Phosphate comes from fish food and sometimes the water. The best way to control phosphate is to seek professional help. These professionals will assess the pond and suggest the best ways to keep the conditions optimum.
Aluminum salt can reduce the amount of phosphate in a pond. Aluminum salt will reverse the effects of nutrients on Ponds and Lakes.
Use Of Algae-Eaters
Algae eaters are fish invertebrates like snails and shrimps. Algae eaters will feed on algae, including green algae, carpet algae, black-bearded algae.
Pond Owners need to consider Temperature, size of the pond, depth of the pond, Ph level, Co-habitants of ponds before choosing an algae eater for their ponds.
Some common algae-eaters one can use in their ponds.
Common Pleco
Common pleco is a species of catfish that are voracious algae eaters. They are well known for controlling algae in ponds and tanks.
Pleco is aggressive, so it\’s best that pond owners who intend to use the pleco give them at least 1000 gallons of water for territory.
Siamese Algae Eater
Siamese fish belong to the family of freshwater carp, and they inhabit freshwater. It is not a very picky eater and will eat green algae and red ones.
Siamese can be very aggressive, and as such, fish pond owners have to be careful when selecting fish that will cohabit with them. They don\’t do well in icy conditions; pond owners should consider that, especially if the pond is outdoors.
Pond Loach
Pond loach doesn\’t eat algae as much as other voracious fish like the common pleco, But they\’d go under the surface of the water and slowly snack on algae.
Pond loach is perfect for keeping pond algae free.
Chinese high Fin-Banded
Chinese High fin coexists very well with other fishes so that pond owners can rest easy with this fish. Chinese high fins are bottom feeders and eat algae strictly as their main diet, making them excellent algae-eaters for ponds.
Chinese High fins are shark-like fishes, so they grow huge. When stocking this fish, pond owners should make sure that their ponds are enormous to accommodate their size.
Grass Carp
As their name implies, they are grass-eating fish. They are excellent fishes for reducing algae in your ponds because they are rather voracious in their eating habits.
Grass carp will eat about 45% of their body weight daily, making them a very excellent choice. The Grass Carp is fast-breeding and competitive; pond owners must consider that when stocking.
Koi Fish
Many people stock koi fish for their outdoor ponds, but they don\’t realize it is also an excellent algae eater.
Koi Fish eat algae as their main diet. They are tiny fishes and will not do well when kept with voracious algae eaters, like Chinese high Fin-Banded, but even so, the Koi fish is an excellent fish to stock when looking to reduce algae growth in fish ponds.
Twig Catfish
Twig Catfish require a ton of space to hide and eat algae because they are bottom feeders. Twig Fish prefer to be in pairs, and they prefer average temperatures.
Twig Catfish makes an excellent algae eater for those whose ponds turn green.
Florida Flag Fish
Florida flag fish is an excellent algae eater because they snack on multiple algae. They eat the black beard algae, thread algae, and even complex algae.
Florida Flag Fish are generally calm, sweet fishes, but they may be aggressive when spawning.
Otocinclus Catfish
These are small algae eaters; they are very similar to the pleco catfish. They eat algae as their main diet, making them very good for green ponds polluted by algae.
Otocinclus eat brown algae and nips the growth of the algae very quickly. They are peaceful fishes and don\’t like being with aggressive fishes. They thrive better in schools.
Bristle-Nose Pleco
Bristle Nose are excellent algae eaters and very suitable for small ponds. They aren\’t selective and will eat a wide variety of alga.
Bristle-Nose is a very peaceful fish and will happily coexist with other fishes. They can handle cooler temperatures and will thrive at 60-65°C.
With these ways elaborated, fish pond owners should identify the problems causing the green color in their ponds and reduce or eliminate the problem.
Conclusion
Pond turning green is caused by many factors like temperature, Ph levels, pollution, and uncontrolled growth of Algae in the pond. These unwanted factors can be reduced and controlled effectively with the methods mentioned in this article.