Keeping Algae from Growing in a Pond

Q: I am desperately looking for a way to stop algae from growing in my small pond with goldfish in it. It is a container pond and I have tried everything. Does anyone have any home remedies?

Thanks in advance,
Michelle

A: Michelle,

Algae multiply rapidly under the right environmental conditions-especially in water containing excess nutrients (phosphate and nitrate) while having access to a lot of sunlight promoting photosynthesis. Effective control requires depriving algae of food and/or light.

Here are a few natural ways to control algae:

Don't overstock your pond with fish. Decomposing organic waste from fish provides a continuous supply of nutrients for algae bloom and string algae. Keep your pond clean by regularly vacuuming the bottom to prevent build up of these nutrients along with frequent partial water changes.

Shade can be supplied with plants such as water lilies and water hyacinth. However, because the pond's primary source of oxygen is at the water's surface, too many surface covering plants can result in low oxygen levels (signaled by gasping fish). You'll need to provide additional aeration and/or reduce the number of fish in your pond if you want to maintain extensive surface-covering plants.

Consider shading the pond's surface with a type of canopy made from shade cloth or lattice. Many aquatic gardeners find this inhibits growth of algae while protecting flowering aquatic plants from excessive sunlight and heat. This method will also protect your koi's colors and protect them from overhead predators.

If all fails, there are a number of algae controlling additives available that are safe for fish and aquatic plants.

Answers:

Keeping Algae from Growing in a Pond

pine straw (07/17/2005)

By ken.

Keeping Algae from Growing in a Pond

Cover at least 60% of the top of your pond with water plants, they will starve out the algae. Also keep pond shaded as sunlight promotes algae growth. (07/18/2005)

By Delinda Harmon

Keeping Algae from Growing in a Pond

Try throwing a handful of new copper pennies in. The copper sulfate discourages algae growth in water. I use them in my aquariums. This is not an "instant" fix, takes a little time for copper to leach out of pennies, but it does work! Happy gardening.
Joyce (07/18/2005)

By Joyce

Keeping Algae from Growing in a Pond

I have been having the same problem with my small pond (100 gallon). I resorted to taking the pond out and pressure washing it, then when I put it back in and refilled it i started treating it with "ALGAE DESTORYER ADVANCED". A big bottle of it at Walmart sells for $8.93 and it only takes 2 teaspoons every 3 or 4 days to treat a pond the size of mine. So far the water is staying nice and clear and the fish seem healthy (its safe for fish and plants). (07/20/2005)

By teresa

Keeping Algae from Growing in a Pond

Find some small pelleted food for your fish. Only give them enough food that they can eat in 5 minutes. I have a small pond and I don't feed the fish every day. I was told that if you have some floating pond plants in your pond the fish will find enough food to live on for several days. Also you might try to find some "water shade" tablets. They turn the water a beautiful shade of dark blue and that helps keep the sunlight out so the algae won't grow so much. I found some water shade at Home Depot in the pond department. Remember some algae growth on the sides of your pond is normal and healthy so don't try to eradicate all of it. Hope this helps. (07/30/2005)

By Jeri