** This post contains affiliate links that give us a small percentage of your purchase for our recomendations. **

If you have any experience with keeping koi in large outdoor ponds, you’ve had some experience with algae. Controlling it is not always an easy task. Throughout your struggles, you’ve probably heard something about barley for ponds. How does this work and what’s it all about?

The Science Behind Barley Straw in Fish Ponds

The exact mechanism of how barley straw works is still unknown. As the barely straw breaks down, it releases compounds that keeps algae from growing, especially string-type algae. Although it will stop the growth of algae, it will NOT kill it. Killing algae will need an additional UV filter or chemical additives.

Is barley straw safe for fish?

Barley straw is the safest algae deterrent available for koi ponds. Adding barley with a UV light will take care of the bulk of your algae problems.

What is the difference in the formulations?

Most products involving barley come in three forms: hay bales, pellets or liquid. The hay bales should be kept in a mesh bag to keep the individual straws from floating into your filtration. Pellets are usually compressed hay in shorter lengths. Both the full bales and pellets will take 3-5 weeks to start being effective. The barely straw needs to be broken down in order to start stopping algae. Liquid extracts bypass this step by doing the breakdown in advance.

When should I add barley straw to my pond?

The best time of year to add barley is before your warmer months and throughout the summer. By starting to use the barley straw prior to the biggest algae growth season, you can stop growth before it starts. Read the instructions carefully on any product before you start to use it.