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How to use Seachem Clarity to clear up green water

In addition to helping with cloudy tank water, Seachem Clarity can also be used for green water. To find out how you can use this product to clear out algae bloom, you can take a look at this tutorial from Aquarium Blueprints.

Why your tank water is turning green

The main reason your tank is turning green is due to an algae bloom, which occurs when you have excess lighting, nutrients and nitrates in your tank water.

How Seachem Clarity will clear out green water

Seachem Clarity will bind the free-floating algae in the water column into large clumps. These clumps will then be filtered out of the aquarium by mechanical filtration.

How to use Seachem Clarity for green water

In order to clear out the green water in your fish tank by using Seachem Clarity, we recommend that you take the following steps:

1. To begin, we suggest that you do a small water change. A water change will help dilute the excess nutrients and nitrates you have in your tank water. As a result, you will be able to clear out the green water faster.

When doing a water change, we recommend swapping out no more than 20% of the tank water volume at a time to avoid overstressing your pet fish.

When removing water from your tank, you should also rinse your mechanical filter media with the outgoing water. By doing so, your sponge will be more efficient at trapping the clumps of algae created by Clarity.

2. After doing a water change, you can dose Seachem Clarity directly in your aquarium.

In terms of dosage amount, Seachem recommends that you add 5 mL, which is a capful, of Clarity for every 20 gallons (or 80 liters) of tank water.

3. While the green water may look worse initially due to Clarity binding the free-flowing algae together, it should start clearing up shortly afterwards.

It can take up to 2 hours for your green water to become clearer.

4. If you are still seeing green water after 24 hours, then you can repeat the first three steps over and over again until your tank water starts to clear up completely.

To speed up the process, we recommend adding polishing filter pads in your filter as this media type is better at trapping algae when compared to sponges. You should also clean or replace any mechanical filter media that are dirty.

How to prevent your tank water from turning green

In order to prevent your tank water from turning green in the future, you can try doing the following:

  • Feed your pet fish less in order to reduce nitrates.
  • Add live plants to your aquarium as doing so will also keep the nitrate levels in check. Plants will also consume the same nutrients as algae, which should lessen the algae bloom.
  • Avoid placing your fish tank in direct sunlight or overexposing it to aquarium lighting for too long.
  • We also recommend adding snails as these will help consume any algae that appear on the surface areas inside your tank. We have great success using Ramshorn Snails with keeping the algae in our fish tank in check.