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What can I do to prevent string algae from growing in the winter?
ASKED BY: Bonnie of Hazelton, PA
ASKED BY: Bonnie of Hazelton, PA

What can I do to prevent string algae from growing in the winter?


A: Even in the cold of winter, string algae can grow in your water garden. All that green nuisance needs to thrive is the right amount of nutrients and sunlight. So what can you do to prevent it? You have three options in your pond management toolbox: Seasonal Defense, barley straw extract, and a three-in-one pond tool.

Boost Your Bacteria
First of all, you'll need to control the nutrients – or the food that the algae eat – in your pond. Because the beneficial bacteria that break down those nutrients go dormant in the winter, now's the time to add some Seasonal Defense (as long as your pond isn't frozen over, of course). It contains bacteria that prefer cooler temperatures. They'll accelerate the decomposition of leaves, scum and sediment that feed algae, reducing its growth to a minimum.

Add Barley Straw
If you have a small water garden, like a koi pond that's less than 10,000 gallons, The Pond Guy Barley Extract provides an all-natural solution for maintaining clean, clear water throughout the winter. Available in bales, pellets and as an extract, it works by releasing compounds that improve water clarity, leaving you a clean and clear pond. The extract form is easy to use: Pour directly into the water and repeat every few weeks.

Manually Remove It
Should string algae form, you can manually remove it by wrapping it around an algae brush, like the one included in the 3-in-1 Interchangeable Pond Tool, and yanking it out of the water. The telescoping handle will add 5 feet to your reach, allowing you to reach those hard-to-access patches of weeds.

Unfortunately, if ice is covering your pond, there's not much you can do to remove that string algae. Plan on removing it during your spring clean-out process. The sun will return soon enough!