by Ellen Feld, author of equine articles
and the "Morgan Horse" kids book series available at www.willowbendpublishing.com
What makes algae thrive in your water? “The key conditions,” continues Woode, “are nutrients, warmth and moisture. Warmth can be provided by the heat of the sun which is why algae in troughs out in a pasture grows faster than in a bucket in the barn. Nutrients can come from horse droppings in the water as well as hay, feed or leaves left in the water. Horses on pasture will also frequently come to a water trough with pieces of grass in their mouths. Nutrients from these plant parts are then released into the water. Also, if your water comes from a spring, or pumped from a pond or any other natural setting, it is more likely to have algae growth than water that is coming from a city water system. The pond water usually has nutrients in it to feed the algae whereas the city water will take a little longer time to accumulate enough nutrients to support significant algae growth.
“Another ideal condition that buckets and troughs offer is that the water is stagnant. Algae grows better in stagnant than fast moving water. So if you have a pond, consider installing an aerator in the form of a fountain or bubbler to reduce chances of an algae bloom. Occurrence of algae problems also depends on the management style of upstream properties. Over fertilized lawns or pastures are major sources of pollutants that support algae in ponds.”
BUCKET & TROUGH SOLUTIONS
Woode insists that if you have algae growing in your buckets and troughs, then your watering system is not good enough for horses. “Good management,” notes Woode, “requires that you keep your water as clean as possible and change it every two to three days. If you change it that frequently, then there is little chance of algae establishing itself. You need to empty the bucket or trough and scrub it to remove any budding growth. However,” warns Woode, “if you just top off the container, you will have problems with algae because the remaining water may contain cells, younger growth or fragments of algae that will readily establish a new colony. People who use large tubs frequently just top them off because it is time-consuming and messy to empty. No matter what the containment is, it is imperative that you dump the water out, scrub, and re-fill with fresh water. Again, you need to do this every few days for buckets and at least once a week for large troughs.”
What if you still can’t
get rid of the algae? Many people report success by adding
apple cider vinegar to the water. “It works by
dropping the pH,” explains Keith Diedrick, extension educator
with the Ohio State University Extension Office.
Most chemical treatments are copper based and sold under different trade names. Unless you are proficient in chemical applications, Woode advises to use products with copper complexes rather than copper ions as the active ingredients. “Copper sulfates [copper ions] in the concentrations needed to kill algae will also kill your fish and all lower level organisms. To be on the safe side, when you use any of these solutions, it is best to treat a portion of your pond at a time instead of the whole pond. That way, if the chemical concentration becomes a threat to your fish population, they can migrate to other sections of the pond and survive. In contrast, when you use a copper complex it won’t harm the fish because it is a slow release chemical and not as harsh on organisms. But it is just as effective at killing the algae. Your extension agent should have a manual to identify the different types of algae. Once the algae is identified, your agent can give you a list of appropriate algaecides and rate them for you, from excellent to good to fair. If any chemical control is used, it is very important to determine how long such water bodies should be kept without being used as watering sources for your horses.”
For those who prefer a non-chemical solution, there are several options. The first is the use of grass carp. These large (up to 50 pounds), long-lived herbivorous from the minnow family are vegetarians with enormous appetites; and they love algae. Be aware that because these are non-native fish, a special permit may be required before releasing them in your pond. To prevent spread of the carp to other water supplies, there is a sterile triploid form of grass carp now available.
Another option is the use of barley straw, which has been popular in Europe since the early 90’s and is now being used in the states. Many pond management companies sell it in rolls and when added to the bottom of the pond, it releases a chemical that impacts the pH of the water and reduces the potential for new algae growth (it doesn’t seem to be useful for existing algae). The use of barley straw is not believed to be harmful to horses but check with your veterinarian.
Controlling algae is
a constant struggle. But with good management practices, it can
be controlled and even eliminated.
Use of the terms "Ultimate Horse Site", "The Ultimate Horse Site", "Ultimate Horse", "UltimateHorse", "The Ultimate Horse" have been in use since 2000 and use of variations of our name for any reason is prohibited.