What Is A Pond Flocculent?

It’s a fancy sounding word that a lot of pond owners may never have heard of, but it can do a lot for your water garden.

A floccu-what they may ask?

Flocculent. Look it up in any dictionary and you’ll get a variety of definitions.

The main one we’re concerned with though is the definition “to flock” or group together.

Flocculents create a chemical, and I use this term loosely because chemistry can involve organic substances too, but they create a chemical reaction that binds or groups various things together. Where this applies to ponds is in regards to floating elements like particulates that can lead to murky or cloudy water.

Green water, which we’ve talked about a lot before(namely here), is made up of many single cell algae, and these can be flocked together as well. But why would you want to do that?

Well what’s interesting about green water is that there are times when these algae are so small that they can pass right through a biofilter and remain in the pond. They can also grow or expand in number quite quickly too. But if they’re not easily removed from the system, then a flocculent can bunch them together in bigger masses, and this helps a filter remove them more readily.

The same thing goes with dirt particles, or light floating particles that will create dirty looking water. These can get trapped in a filter, or in other cases, they become stuck to one another and get heavy enough to sink to the bottom of the pond. In either case, they are cleared from the water column and the pond will become clearer and less dirty or murky.

So in a strict sense, a flocculent can work as a pond clarifier.

Two Common Types Of Flocculents

Although there may be others, we’ve worked exclusively with two types of flocculents over the years. For smaller ponds I like to use an organic formula called Acurel and it does a very good job of adding clarity to a pond that’s having issues with green or murky water.

In larger ponds a commonly used additive would be Alum, or Aluminum Sulphate which also acts as a binder to various things, including phosphates, which help to nutritionally support algae growth. I no longer suggest using Alum in smaller ponds since there are better options in my humble opinion. On larger waters where fish are concerned, be sure to read label directions and test your water first to ensure that the pH and other particulars of your water chemistry are in order. And as I often note, it’s always a good idea to have ample aeration going whenever you treat a large pond with anything.

Do You Need A Pond Filter For This To Work?

A common question that comes up in small pond usage is “do we need a filter for a flocculent to work”? And the answer is not really, but sort of. Let me be more specific. You won’t need a filter in order for something like Acurel to work, but you’ll probably want to try and remove what you can of the material that’s clumped together, and a very fine net would likely suffice. If you have access to a light duty pond vacuum, these can also help remove any material that’s been pulled to the bottom of the pond.

So for various kinds of water clarity issues, a flocculent may be worth a try to clear things up. For some ponds that have a very chronic problem specifically with green water I’ll normally look to add a UV or ultraviolet clarifier light to the mix but a flocculent can still end up being a very good short term option in order to see your fish once again.