Keeping Algae Under Control
Discussions allow retailers to talk about products, tank conditions and fish.
By John Tullock
Controlling Algae with Herbivorous Fish
Some freshwater aquarium fish feed on algae and can help to keep the tank looking tidy.
• Otocinclus catfish: Many species of these small South American cats exist, and all are ideal algae-eaters for small to medium community tanks.
• “Plecostomus” catfish: The durable suckermouth catfishes, Hypostomus and some other genera, spend most of their time scraping algae off the tank glass, and are great choices for medium to large community tanks.
• Farlowella catfish: These South American species feed exclusively on algae, but are a better choice for experienced aquarists, being more delicate than other herbivores.
• Freshwater “sharks”: Members of the genus Labeo, including L. bicolor, the popular red-tailed “sharks” eat a lot of algae, and are good choices for tanks with larger, more aggressive fish. Saltwater tanks have some good choices for algae-eaters.
• Yellow tang, Zebrasoma flavescens, and sailfin tang, Z. veliferum: Both spend every waking minute cropping algae from solid surfaces.
• Foxface rabbitfish, Siganus vulpinus: This fish is too large for tanks less than 50 gallons but eats filamentous algae almost exclusively.
Algae grow in every aquarium. Their presence might indicate poor water quality, but may also mean everything is proceeding normally. Controlling undesired algae requires understanding what causes their appearance. For each situation, remedies and tools exist to help aquarists manage algae growth—and to provide retailers with sales opportunities.
The best-maintained tank, whether freshwater or saltwater, will develop green algae on the glass, the rocks and any solid surface. This growth seldom does harm, but it may obscure the view into the tank. For routine removal, manufacturers have come up with dozens of tools. For many years, the algae scraper of choice was a steel or hard plastic blade on a long plastic or wooden handle. This design allows hobbyists to scrape the glass without getting their hands wet.
Another design, consisting of two magnets, one with an abrasive pad and one with a felt pad, came along about 25 years ago. The magnet with the abrasive pad goes inside the tank against the glass, while the other one is held against the outside of the glass by magnetic attraction. Moving the outside magnet causes the inside one to follow, scraping off the algae.
“Algae removal is a part of daily, routine maintenance for every aquarium,” says Mark Hanson, owner of Algae Free LLC, a manufacturer of magnetic algae scrapers located in Madison, Wis. “Besides being unsightly, algae can cause permanent damage to an acrylic tank if it is not removed regularly.”
When a hobbyist first sets up an aquarium, the tank is likely to experience a series of successive algae “blooms” for the first few months. Water chemistry fluctuates during this time, accompanied by a buildup of nutrients. Various species of microscopic algae enter the tank via their spores, always present in the air. Since a new aquarium offers “virgin territory,” these algae may experience explosive growth.
They exploit the nutrients in the water, quickly coating the glass and decorations with a green, brown or reddish film, or even tinting the water green. With proper maintenance, this type of algae growth usually subsides within six months as the aquarium matures. Novice customers may panic at the rampant growth, certain that something is wrong.
Retailers can help customers understand this process and recommend products for routine algae removal. This strategy helps the beginning hobbyist develop good tank maintenance habits right from the start.
When to Be Concerned
Algae blooms that appear in a well-established tank can be cause for concern. Sometimes slime algae threatens to cover everything in its path. In a reef tank with delicate invertebrates or a freshwater tank with many living plants, this kind of rampant algae growth can lead to disaster, smothering desirable organisms under a layer of slimy goo.
Slime algae, or cyanobacteria, can be treated with tank additives, says Ron Johnson, president of Ultralife Reef Products in Shelton, Conn. When algae are already present in the tank, products designed specifically to treat the problem offer a simple answer for hobbyists. Johnson emphasizes the importance of knowing the type of algae present and choosing a product made specifically for that type.
If the algae return, the aquarist may need to take more drastic measures. A too-high concentration of dissolved phosphate may have accumulated in the tank, providing fertilizer for the algae. Or poor maintenance has led to an accumulation of various waste compounds, and these, too, are feeding the algae growth.
Assisting the Customer
Helping customers discover the source of these kinds of algae problems is a good way to ensure return business, says Bruce Davidson, owner of Sandy’s Pet Shop in Louisville, Ky. Davidson offers his customers several suggestions for minimizing the buildup of wastes in the aquarium.
“Remember that the aquarium is a closed system and what an animal eats, it also poops,” he says. “Some of the nutrients are metabolized and stay with the animal, but the majority will be available for more algae growth.”
He suggests cleaning particulate filters at least once a week, making sure protein skimmers are clean and adjusted properly and changing activated carbon monthly.
He also recommends a commercial phosphate remover if tests show the tank has excessive phosphate.
Ken Stevenson, aquatic manager for The Aquatic Critter in Nashville, Tenn., says he prefers to begin any diagnosis of an algae problem with a water test.
“We urge customers to test their own water regularly, but we will also do water testing for them,” he says.
With the test results in hand, staff are better able to tailor their advice to the individual customer’s specific situation.
“I prefer that customers try water changes first, and then proceed with other control methods if that does not work,” he says.
Stevenson says the store sells lots of phosphate- and iron-removing products to help customers with algae control.
Experienced retailers agree that they like to include herbivorous fish or invertebrates, depending upon the type of aquarium, to help control algae.
“In the freshwater aquarium, I like the flying fox, rosy barbs, Otocinclus, mollies and the clown plecostomus,” Davidson says.
For marine tanks, he suggests up to one blue leg hermit per gallon and one turbo snail per 5 gallons. He recommends herbivorous fish such as tangs and rabbitfish for algae-patrol duties.
Algae grow in every aquarium. Helping customers keep the situation under control can provide numerous sales opportunities. For everything from fish to scrapers and additives, a green aquarium can lead to green in the cash register. <HOME>
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