Will Algaecide Kill My Fish? Protecting Your Pond From Overdosing
Using Algaecide in Your Pond
Algaecide is a chemical treatment applied to ponds to kill algae and prevent its future growth. This treatment typically works quickly, clearing up algae within days. However, it's essential to choose the right type of algaecide—some are safe for fish and plants, while others are not. Always read product labels carefully to make sure they are safe for your pond.
When using algaecide, make sure to maintain high oxygen levels in the water. Algae naturally produces lots of oxygen, which we have to be thankful for as we breathe algae-produced oxygen. Your pond is no exception. As algae treatments kill the algae, they also deplete oxygen. It’s recommended to run an aerator during treatment to protect your aquatic plants and fish. Treat your pond in parts, section by section, to avoid over-treatment, which can be harmful to your pond's ecosystem. Start at one end and treat a section every few days.
After treating your pond, it's necessary to remove the dead algae, which sinks to the bottom and can release toxins into the water. A muck shovel, a heavy-duty net, and your bare hands can all be used to remove the dead sludge. Additionally, algaecide disrupts beneficial bacteria in your pond. To balance this, introduce good bacteria after every treatment to help maintain a healthy balance and prevent future algae outbreaks. Algae is blooming because it has the best conditions for growth. By adding beneficial bacteria, you will create competition for the algae.
Considerations for Smaller Ponds
For smaller ponds, using algaecide might not be ideal due to the high concentration of chemicals involved in such a small environment. These products are generally more suitable for larger bodies of water, where the dilution factor reduces potential risks.
Other Algae-Removal Methods
Algaecide alone won’t solve your problems. There is an imbalance problem in your pond showing itself through excessive algae growth. Finding out how to re-balance your pond will remove the need to attempt extreme chemical methods.
Manual Algae Removal
Removing algae manually is a practical first step in controlling algae in your pond. Carefully using a rake, muck shovel, and your hands, you can clear floating algae from the surface. However, this is primarily just part of standard pond maintenance, and in the case of a bloom, simply removing the overgrowth rather than the literal root of the problem. Getting rid of the floating and string algae will only remove the visible surface issues but not solve the problem. Manual removal is best used as part of a broader algae control strategy.
Pond Plants
Pond plants are a natural and sustainable option to prevent and control algae over time. While they don’t work as instantly as chemical treatments, they compete with algae for the same essential nutrients, reducing the nutrient resources available for algae growth. As these plants thrive, they absorb excess nutrients more rapidly, thereby limiting the nutrients available for algae. Surface floating plants such as water lettuce and water hyacinth, and plants with floating surface leaves such as water lilies, also block sunlight and reduce water temperature. Sunlight and warm water is one of the things green algae loves most. By limiting sunlight penetration, these plants hinder algae’s ability to photosynthesize and grow.
Plants perform this double-duty of nutrient competition and shading in your pond and are one of the most effective methods of algae control long-term. Whatever method you choose, don’t neglect adding a few plants to your pond.
Cool Down the Pond
While pond plants naturally cool your water down, you may need to look outside your pond. Adding some shading trees and bushes, privacy fence, and even a sun sail over a portion of your pond may be additions you’ve been looking to make anyways. Use the area around your pond to lower your pond’s temperature and inhibit algae growth the same way as aquatic plants would. Before installing something new around your pond, make sure you’re not creating another issue down the road. You don’t want to plant a shading tree only to realize years later that the leaves are uncontrollable in the fall because of where you placed it or the type of tree it is. Add shade wisely!
Pond Dyes
Pond dyes are anther method of shading your pond by limiting sunlight penetration into the water. By coloring the water, these dyes prevent sunlight from reaching the algae, inhibiting their growth. It’s important to choose pond dyes carefully, as some may contain chemicals harmful to your pond. While not the best solution, this may be what’s needed in a select number of cases as a band-aid until the system can correct itself.
Algae Eating Fish
Incorporating fish that consume algae can be another effective method to control algae in your pond. Classic pond fish such as koi and goldfish naturally graze on algae. However, don’t expect this to be your only algae-control method. Fish only eat when they’re hungry and only small amounts at a time, so you’ll need some patience. While algae-eating fish help with maintaining control, it’s best to use other methods in addition to fish.
Do also keep in mind that too many fish can contribute to algae issues as well. Algae loves excess nutrients. Adding more fish than you pond can support will only exacerbate your issue.
Monitor Fish Feeding
Overfeeding your fish can lead to excess nutrients in your pond. To control algae growth, only feed your fish only as much as they can consume within just a few minutes without leftover food. Reducing food encourages fish to eat algae, helping keep your pond clean. Too much of anything can be a bad thing, and leftover food in your pond is no exception.
Use Yard Treatments Responsibly
Algae thrives off excess nutrients! When too many chemicals and growth additives leach into the water, algae can go into a growth frenzy, what we know as algae blooms. You might notice how many of our Minnesota lakes and ponds around the Cities are green, not blue. This is the result of too many yard treatments being washed away into our lakes through rain and everyday irrigation and sprinkler systems. While the best thing would be to avoid yard treatments altogether, watching where you spread it and giving yourself good margins around the edges of your yard and runoff areas will ensure that local water systems stay clearer and keep your own personal backyard pond in better shape.
Beneficial Bacteria
As mentioned above as an important part of a post-algaecide treatment, beneficial bacteria is a microscopic ally of yours in the algae fight. Introducing beneficial bacteria into your pond is an effective way to control algae naturally and keep yourself from having to continually treat your water. This bacteria competes with algae for nutrients, effectively reducing the algae’s ability to thrive. While this method doesn’t provide immediate results, it’s excellent for long-term algae prevention, especially in new ponds which often lack beneficial microbes due to filtered water. Adding beneficial bacteria right after setting up your pond can prevent initial algae outbreaks. Whether you currently deal with algae or not, beneficial bacteria is part of every healthy pond ecosystem.
UV System
UV bulbs are one popular method of temporarily clearing your pond of algae. They work by exposing algae to strong UV light, effectively killing the cells and preventing future growth. This method targets blue and green algae during all growth stages. Do be aware that a UV system will kill everything that passes through its system, including beneficial bacteria. Make sure you install a UV system in the correct place so as not to kill your pond ecosystem. Regular cleaning of your filter is also essential, as large pieces of dead algae can clog the system, leading to inefficiencies and potentially unhealthy pond conditions.
IonGen System
Similar to a UV system, an IonGen system only targets algae. IonGens effectively kill algae without the use of traditional liquid chemicals, and continue controlling algae growth throughout the entire system by using a microprocessor that sends a signal to its ion-producing probe. Safe for your fish, plants, and beneficial bacteria, you may find this system easier to install and manage than a UV system.
Balancing Your Ecosystem
As you’re finalizing your plans to control your pond algae, Don’t forget to carefully monitor the balance of your ecosystem. Balance really is the right word here. Your algae bloom is the result of an imbalance, this guide is intended to set you back on track to getting re-balanced again!
If you’re looking for more ways to keep your pond clear, continue reading our Secrets To A Clear Pond