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Pond - Clears Green & Cloudy Water

Pond - Magiclear
Green and cloudy water, build up of algae


When to use?
When water appears green and/or cloudy. Magiclear causes particles in the water to clump together which can then easily settle out of suspension or be removed by the filter.

How to use?

  • Test the pH and KH of the water.
  • Aerate pond well e.g. fountain, waterfall or air pump. Conduct a partial water change (as much as is practical) before use, especially if the water is extremely green, like “pea soup”.
  • Switch off pump only if strong flow rate could prevent particles from clumping but remember to switch back on as soon as water clarifies.
  • Mix the correct dose in a clean bucket of pond water, then pour evenly around the pond.
  • Clean the collected particles from the filter after treatment.

Without a filter, some clumps may float and can then be removed using a net. Use when you have plenty of time to observe the fish and take action in the unlikely event of a reaction.

Do not:

  • Do not use when the dissolved oxygen may be low (e.g. at daybreak, in hot, humid or thundery weather, or within three hours of feeding).
  • Do not use if the KH is below 6 or the pH is below 7.
  • Do not use if there is nitrite in the water.

Failure to conduct a partial water change on extremely green water, like “pea soup”, may result in a rapid reduction in oxygen which could be dangerous to fish! For more information on this subject visit our knowledge hub.

Q: How does Magiclear work?
A: Magiclear is a flocculant, meaning it causes particles to clump together. These clumps can then be netted out if they are afloat on the surface or they will be caught by the filter as the water cycles through it.
Q: How long does Magiclear take to work? A: Typically, you should start to see an effect within the first 24 hours of adding Magiclear. However, extreme cases of green water can overwhelm the product. Performing a water change before adding Magiclear will help cool the water, increase the oxygen carrying capacity, and dilute both the algae and the algae-causing nutrients, all of which will improve the likelihood of the products' success and keep your fish safe during the treatment. Generally, we’d recommend performing a water change of approximately 30% (or at least 50% in severe cases) before dosing the pond with Magiclear.
Q: How often can I repeat the treatment? A: After dosing, you should wait 7 days and perform a partial water change before re-treating. You should also ensure that you clean out the filters after the 7 days to prevent the collected clumps of algae/bacteria from clogging the filter and breaking down to cause ammonia and nitrite spikes.
Q: I have added Magiclear to my pond, but nothing seems to be happening. What's gone wrong? A: This could be down to a variety of factors. Firstly, if the pump is too strong, this can break up the clumps of matter as quickly as they form. Try turning down the flow rate a little and see if that helps. Secondly, it may have been working but the filter has ‘caught’ the maximum amount of matter that it can physically contain. Try emptying and cleaning the filters and see if things improve. Thirdly, the problem may be too large for the Magiclear to cope with. In very bad cases, any effect of the Magiclear may be counteracted by the sheer density of algae or bacteria. Try performing water changes to reduce the biological matter and then repeat the treatment after 7 days. Ensure you perform a water change and clear out the filters before repeating the treatment.
Q: My water is very green, like pea soup! Can I still use Magiclear? A: Yes, you can. However, you must ensure that you perform a water change of at least 50% before adding the product and keep a close eye on your fish.
Q: Why must I do a water change before adding Magiclear to my pond? A: Algae and some bacteria can provide significant amounts of oxygen to their surrounding water as they photosynthesise and go through metabolic processes. As Magiclear works, clumping these particles together and removing them, these particles will stop producing oxygen. If you have a severe algae/bacterial problem, this removal/prevention of oxygen creation can result in a rapid reduction to an extreme lack of oxygen which the fish are not accustomed to. This leads to stress and, if severe enough, can lead to the fish suffocating from the lack of dissolved oxygen. The best way to avoid this is to perform a water change beforehand, replenishing the oxygenated water so this level is reduced to a still-manageable amount. You’ll also remove some of the algae/bacteria during this process too and dilute the remainder, and the addition of ‘fresh’ water will cool the pond allowing it to hold more dissolved oxygen. The greater the water change, the better the treatment is likely to work and the happier your fish will be during the treatment.

For common frequently asked questions, click here.


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Available in the following variations:

250ml, 500ml & 1 Litre

Where to Buy?

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Let us calculate your dosage for you!

To make the process of using our products even easier this handy dosage calculator tells you the amount you will need to put into your system. Please ensure you also read the instructions and warnings that are written on the bottle/pack label.

Note: This calculator does not take into account water displacement such as that caused by substrate, ornaments, water features and plants etc. Therefore, please adjust the calculated volume accordingly.

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You’ll require*
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10ml per 40gallons (182litres)

* Always follow the instructions on the label. This calculator is intended to be used only as a guide to how much product you need to buy to treat your system. It does not take account of displacement caused by gravel, rocks and ornaments etc and does not include the volume of any external filtration system. NT Laboratories Ltd. will not accept any responsibility for inaccuracies or misuse of this guide.

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  • Darren Woolway from Stones Aquatics

    The second product that we find is a real winner for us is Magiclear; if you’ve got green cloudy water in your pond or white cloudy water, this stuff you can literally see it starting to bind all of those particles together in front of your eyes. So, we use it a lot when we go out and do pond maintenance, and last year it was one of our bestselling NT Labs products.