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Getting a Jump Start on Algae Control
Algae can be one of the most frustrating parts of maintaining a pond.  However, by taking proactive steps in the spring to head off algae growth you can begin to spend more time enjoying the natural beauty of your pond and less time maintaining it. 
For those of you new to ponding, there are two types of algae you will encounter:
  • String algae -  are fibrous green strands of algae that can grow out of control if not kept in check. Excessive growth of the string algae removes the oxygen that fish need from the pond water.
  • Green water algae bloom - are tiny algae spores that will cause your pond water to turn green and cloudy.  This is part of a natural cycle caused by an excess of certain trace minerals, nutrients and sunlight.

The first step in heading off algae is to properly clean your pond each spring.  If there is minimal debris on the bottom of the pond, the debris on the bottom of the pond should be vacuumed out with a Pond Vacuum, and physically pull out as much string algae as you can, followed by a 25% water change. Prior to refilling the pond with new water be sure to add a Water Conditioner to remove chlorine and chloramines, detoxify heavy metals, reduce fish stress,  by add essential electrolytes and reduce skin slime coat. 

If you have heavy debris and fish waste on the bottom of the pond (over 1"), it is often easiest to completely drain the pond to remove the debris.  Prior to completely draining the pond be sure to set up a fish holding tank with water from the pond and place in the shade, use an EasyPro Pond Aerator to add oxygen to the water while the fish are in storage and be sure to cover the containers so that the fish cannot jump out and predators cannot access the fish.  Be sure to add the Water Conditioner prior to reintroducing the fish and float the fish in a bag to equalize the temperature if the difference in temperature between the holding tank and the new pond water is more than 5°F. 

To minimize String Algae growth during the summer:
  • Use an algaecide to kill off the string algae you were not able to physically remove. A liquid algaecide, such as AlgaeFix is good for treating algae in the pond.
  • When treating algae on waterfall or stream rocks it is recommended that you turnoff the pump, place an aerator in the pond to provide oxygen for the fish, sprinkle a granular algaecide, such as Green Clean on the rocks and let it set 30 to 60 minutes. Turn your pump back on and have a net ready to catch the algae running into your pond. 
  • Add liquid barley on a regular basis to keep your pond clear and clear. Liquid Barley starts working immediately and is easier to use and less messy than the barley bales .  We recommend Pond Care Barley Clear or  Barley Extract.
  • Regularly test the water using for pH and Phosphate.  High pH and Phosphorus are the leading causes of string algae. For most accurate testing results we recommend Pond Care Master Liquid Test Kit and Phosphate Kit.
  • If the pH is high, use pH Down, followed by a pH Buffer/Stabilizer as needed.  
  • If Phosphorus content is high, use a Phosphate Remover as needed.   
  • Use a Sludge Removing Bacteria to breakdown the remaining organic matter from dead algae on a regular basis. Our top selling sludge removers are: Sludge Buster by Bacti-Pur, Easy Pro Sludge Remover and Microbe-Lift Sludge Away.
  • Installation of a Pond Aerator will also assist in keeping the algae growth down in the pond and your fish happy, because they love the extra oxygen!
To minimize or avoid Green Water Algae blooms this season:
  • Establish a good biological balance in your pond by adding Pond Bacteria and Sludge Eating Bacteria on a regular basis. 
  • Check for high nitrate levels, which can cause green water algae, using a Nitrate Test Kit. If the level of nitrate is high a 25% water change should be performed.
  • Add plants to your pond to deprive the algae of light and nutrients.  To do this effectively, plants should cover a minimum of 66% of the water surface, if the pond is in full sun. Generally, if you have the proper water plant level and the nitrates are in the correct range, the green water algae will clear naturally in a week or two, provided and you are adding bacteria to your pond on a regular basis.
  • A Water Clarifier can be used to clump the Green Water Algae.  While using a clarifier, you should clean your filter and skimmer pads daily, until the water clears.  Our best selling water clarifier is AccuClear made by Pond Care.  This treatment should be combined with using AlgaeFix every 3 days.
  • If your pond is in full sun or you find that you are plagued by green water algae all summer we highly recommend installing an Ultraviolet (UV) Light Clarifier to your pond system to clear the green water algae.  We find the UV Light is the best option to keep your pond water crystal clear throughout the summer. The purchase of a UV light does require an upfront investment, but in the long run it is cheaper than the chemical approach and requires minimal labor once installed.
  • Installation of an aerator also helps in keeping the water clear, gives an extra boost to your water treatments and your fish love the additional oxygen!
By following these simple maintenance steps on a regular basis, you will significantly reduce algae growth in your pond and be able to spend more time relaxing and enjoying the beauty and sound of your pond all summer long. 

For additional information or questions, please feel free to call us at 248-889-8400 or stop by The Pond Place of Michigan.

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