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The Rise and Fall of Algae: Why Does Algae Float and Sink in Ponds at Different Times of the Day?

18th July

Why does pond algae float during the day and sink at night? The answer to why this happens is simpler than you might first think. This blog uncovers the truth about why this actually happens. 

Like any plant, algae produces oxygen in the day during photosynthesis. The oxygen that is released gets trapped between the filaments of the algae, making it lighter and causing it to float to the top of the pond. At night the oxygen production stops and it begins to dissipate, causing the algae to sink back down to the bottom of the pond.

While algae is not dangerous to fish, it can be unsightly and suggest problems within the pond. Continue reading to find out how to combat this algae once and for all.

Step 1: Perform a water test, testing specifically for pH and Nitrates. 

Use a pond-testing pH kit to check the water parameters. A normal pond pH should be between 7.5 and 8.5. If your pond parameters are off, consider using a product such as Envii Pond Equaliser to buffer the water. If the nitrates in the pond are too high, use Nitrate Klear to remove them.

Step 2: Use a bacterial product to take away nutrients

Algae needs sunlight, warmth and a food source to thrive. Removing its food source will prevent it from growing. Use a bacterial product regularly to remove the nutrients in the pond such as Envii Sludge Klear.

Step 3: Use Algae Klear to kill the algae.

Do not pull algae out of your pond unless your fish are getting tangled in it. By pulling out the algae, spores are released back into the water causing the algae to grow back stronger than before. Instead, use Algae Klear Xtra to kill the algae and break it down.

Related Products

  • Pond Algae Treatment - Envii Algae Klear Xtra

    Envii Algae Klear Xtra

    Kills submerged algae and blanket weed.
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  • Front view of Envii Sludge Klear

    Envii Sludge Klear

    Reduces sludge in ponds and clears murky water.
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  • Front view of Envii Pond Equaliser

    Envii Pond Equaliser

    Stabilises the pH & KH in ponds to keep water safe for fish.
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About the author

Olivia Ball

Marketing Manager

Olivia is our marketing manager, when she’s not planning envii’s next big marketing campaign, coordinating the marketing team or working on reports, you’ll find her spending time with her friends, dancing or working on her next travel plans.

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