Can Koi Fish And Pond Plants Co-exist?

As many of you know, green water is a common issue in tons of small fish ponds. And one of the best ways I have always suggested to deal with it is with a combination of beneficial pond bacteria and desirable plants. But there’s a problem with this advice, at least where a Koi pond is concerned.

It’s fairly well known and confirmed by many pond owners that Koi fish love to eat almost anything. This includes some of the more desirable pond plants that you’ll find in most water gardens. Lilies, hyacinth, grasses and so on, are often preferred forage material for the usually ravenous Koi. It’s so common an occurrence that many pond owners just assume the you can’t have Koi and plants in the same pond.

But such is not the case…fortunately.

In fact, while most Koi have an insatiable appetite, not all of them will end up eating plants to any great degree. In some cases it may be because they’re more accustomed, happy, and well nourished by traditional fish food. Or perhaps they just haven’t developed a particular taste for the type of plants found in pond. For whatever the reason, it’s simply not a given that Koi will eat your pond plants into oblivion.

But they can…unfortunately.

So what’s a pond owner to do when your in doubt about it all?

I was recently reminded of the best tactic when it comes to limiting what Koi feed on and it came from one of my kids. We’ve been on kind of a “low carb” diet of late around the household but that certainly doesn’t mean my kids have lost their affection for sweets. Just the other day we walked by our supermarket bakery area and low and behold there was an entire rack full of sugar glazed doughnuts just screaming to be taken home.

The beauty of the display enthralled all of us but we didn’t get our doughnut fix that day. They were protected behind a clear but solid piece of glass and at the time there was no attendant there to help us so we simply moved on down the aisle. No tears, no strife, and no remorse.

And this got me to thinking about Koi. Just like us, they can’t eat what they can’t touch. It sounds simple, but in reality it’s the best defense if you happen to have some vegetarian fish.

Remember…They Can’t Eat What They Can’t Touch!

Words to live by perhaps.

As far as fish go, here’s a few tips to help keep them away from your plants.

One of the best ways to protect some rooted plants is to cover the roots with some fairly heavy and robust lava rock. Many Koi don’t like the rougher texture of the rock and they won’t work that hard to move it out of the way if it’s heavy enough. The plant can still get all the nutrients it needs from the water since the rock is pretty porous. Just be sure to use rock that’s large enough to deter the fish from dislodging it.

In a similar fashion, you can put the plants in various kinds of containers such as plastic baskets that will keep the fish from getting too close for comfort. I’m not necessarily talking about pond plant containers here. Solid plastic box planters, grated crates and buckets come to mind, but with a little creative thinking you can probably find any number of containers that will do the job.

And finally while this may not apply to every small pond situation, if you’re designing a pond, be sure to consider using a bog type filter where the plants and vegetation are in an area that’s completely “off-limits” to the fish, but they’ll still help incredibly with improving the water quality in the pond.

So before you simply write off the idea of having pond plants in your Koi pond, be sure to not assume anything. First go ahead and try them together and see how things go. As it happens in many ponds, the fish may simply decide they like something else better and leave the plants alone. If they do show a preference for a salad, there are still some simple and effective things to try so you can enjoy both pond plants and Koi together at the same time.