Treating A Pond With Green Or Murky Water With A Flocculent

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One of the most common problems we hear about when pond owners call in during the summer months has to do with water clarity.

Green or murky and cloudy water tend to show up as the pond warms up and the degree of coloration can vary from a light tinting to a full blown green or brown where you can’t see your fish any longer.

Many times a good filtration system will help a lot in smaller ponds with this type of problem because depending on the color, the issue could be an actual algae issue, or it could come from a lot of suspended material in the water. As long as the filter is adequate and the particules or algae cells are big enough, they’ll get filtered out in good order. The problem is, not every filter is equal to the task, and to make matters worse, some of these cells and particles are pretty darned small. Sometimes they’re so little that they can pass right through the filter without being taken out. And when this happens you won’t see much of a change in your water quality.

If you’ve watched several of our videos on dealing with green water algae, you know that one of the useful tools for dealing with the problem is uv or ultra violet light. This device emits light which radiates the algae that passes in front of it and this damaged the algae cells to the point where they either die off and/or become damaged and clump together in larger masses which ultimately leads to better filtering.

UV is very useful in this regard and we often do recommend it for chronic green water issues, but like every mechanical addition to a pond it does have to be installed and it costs more than just some pocket change. Oh and one other thing…if the problem is more like a murky or cloudy water, uv light may not help with that at all.

So is there anything else that might help with green and murky water?

In short, the answer is yes. Using something called a flocculent may very well help.

By definition a flocculent creates a reaction that is “aggregated in woolly cloudlike masses”. For our pond purposes, what this means is that a “floc” for short, will make little things in the water accumulate in larger masses. This includes small single cell algae and suspended particles of organic material.

Some of the more common flocculents found in the pond industry include aluminum sulphate or “alum” and this is often used in larger ponds to help clear the water column and bind nutrient based phosphates together to help reduce some algae issues. A common brand name for alum is Phosclear.

Another type of flocculent that you’ll sometimes find used in small ponds, and koi ponds in particular is called montmorillonite clay. This product will help clear the water and aid in fish health as well.

And finally our preferred flocculent for small ponds is somewhat old, and new. Acurel is actually a product that’s been around for 40 years or more and it’s been used in the aquarium industry through that time. Recently the product has been formulated for use in ponds and it’s very effective at creating this clumping action with green water and suspended solids in the water column. It’s completely organic, safe for fish, and meets our requirements for being an eco-friendly and useful product.

We generally recommend Acurel over any type of algaecide where green water algae is concerned. If you don’t have a UV light, Acurel may be able to achieve a similar response and allow your filter to be more effective. You’ll want to clean your filter after using it and a follow up treatment can be applied within 24 hours.

If you don’t have any type of filter running for your pond you can still use Acurel, but you’ll want to use a skimmer net to remove any clumps that form.

Click the following link to learn more about Acurel.

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