Friday, June 17, 2011

A Friendly Addition to Your Pond: The Plecostomus

     Have you ever lifted up a rock in your pond, only to realize that your hand is covered in a stringy, green slime? Ah, the infamous string algae. This type of algae can reach such a length that it gains the appearance of hair or string. On a peaceful note, string algae is actually relatively easy to control once you realize how.

     Plecostomus, Hypostomus plecostomus, plecos, plecs, algae eater, sucker fish…(what ever you want to call it) is the miracle worker of a pond suffering from algae blooms. Being omnivores by nature, these fish absolutely love to eat string algae. In fact, the only algae they do not eat is the algae they cannot reach…i.e. the algae on the waterfall. In medium ponds, you may do well with two plecostomus; however, you may want to buy larger plecostomus if your pond is larger than twelve thousand gallons. For small ponds of two or three thousand gallons, two small plecostomus will do the job. If you have a pond smaller than two thousand gallons, baby plecostomus will work best.

     At the end of a growing season, plecomstomus will grow over a foot long. Since they are tropical fish, plecostomus cannot survive in outdoor ponds in the winter if the water temperatures drop below 55 degrees Fahrenheit. If you are interested in buying plecostomus for your outdoor pond, the best time to do so actually depends on the time of year (generally towards the middle/end of spring) when the temperature of the water in your pond is above 55 degrees at night.

     In very small ponds, plecostomus are generally very aggressive. If you have a pond of less than 600 gallons, a pair of plecostomus would not be your smartest choice. Another factor that plays into your decision in buying a pair of plecostomus for a small pond is if you have any other pond fish besides koi. Goldfish, being a slow moving fish, may become the chef’s special on the plecostomus’s lunch menu because of their appealing slime coat and scales. However, plecostomus would much rather eat algae than chase around fish, given the choice. Not only do plecostomus eat algae in your pond, but they also feed on leftover food that your koi do not eat. If leftover food in a pond is not eaten, it will eventually turn into ammonia. That being, plecostomus also solve an ammonia problem. On a side note, if your pond is experiencing high ammonia levels, it is imperative that you restore the level to normal. High ammonia levels are very toxic to fish. For more information on ammonia control, read our article about ammonia and the water cycle.

Johnson, Erik L. "Plecostomus String Algae Control." Koi Vet. Web. 3 Mar. 2011. .
Controlling Algae." Pond Systems - Kits, Supplies and Koi. Web. 01 Mar. 2011. .
"Getting Rid of Algae in Koi Ponds | The String Algae Blues." Japanese Koi Fish Guide. Web. 01 Mar. 2011. .
Johnson, Erik L. "Plecostomus String Algae Control." Koi Vet. Web. 3 Mar. 2011. .
"Koi Pond Filters – Keeping It Clean As Nature Intended | Koi Pond Garden." Koi Pond Garden | Koi Fish Pond Care and Maintenance. Web. 01 Mar. 2011. .
" Medicine. Web. 01 Mar. 2011. .
"Plecostomus." Wikipedia, the Free Encyclopedia. Web. 03 Mar. 2011.

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