4 Reasons Your Waterfall is Foaming

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Picture this, about two months ago you just finished having a beautiful waterfall installed into your backyard. The water was perfectly clear a few weeks ago, and though your maintenance routine hasn’t changed, now you’re beginning to notice foam build up at the base of the koi pond. Where did all of this foam suddenly come from?

Waterfalls begin to foam when there is an excessive amount of organic material in the water. This material buildup is almost always the result of overfeeding the fish residing in the pond, too many fish living in the same pond, inadequate filtration, or a runoff making its way into the pond.

If you’re still scratching your head wondering what exactly an “excess of organic material” means, don’t worry. You are not alone! Let’s break it down a little further.

What Does Excess Organic Material Mean?

The icky foam that is now being produced from your once-crystal-clear-waterfall has a simple explanation. That explanation is too much protein. When organic matter, like fish food or feces, breaks down, protein builds up in the water. Then, when that protein-rich water is exposed to the air, foam is created, thus giving your koi pond that nasty, swampy, bog aesthetic.

This excess of protein can be the result of too much, uneaten fish food decomposing in your pond. It could also simply mean that you have too many fish sharing the same pond. Another explanation for this foam could be that your filtration system just isn’t doing its job right. However, it could also mean that there is a source of runoff water making its way into your pond or waterfall.

Is the Foam Really a Problem?

Now that we’ve covered how and why this foam is suddenly plugging up your pond, it’s time to ask the lazy-man question. Is it an issue worth fussing over? While certainly not the most visually appealing, is the foam that your waterfall is producing really a problem? Is it a potential risk to the overall health of your fish or is it just a bit of an eye-sore?

Foam is not an immediate health risk to your fish, but it can, however, be a sign for bigger problems farther down the line.

Solving the Foaming Problem

Increase Filtration with Pond Plants

You can boost the filtration of your pond by adding aquatic plants to it. Aquatic plants will help filter your pond due to the amount of oxygen they produce within the water. Some of the best plants to use to increase the filtration of your pond are water iris, taro, canna, pickerel rush, watercress, water hyacinths, and hornwort.

These plants combat ammonia, a product of fish waste, and nitrates, which accelerate algae growth. Both of which will help in keeping your pond gunk-free.

Relocate Your Fish

Too many fish in a condensed area, could easily be the root of your foam problem. When there is an overpopulation of fish in one pond, the waste builds up fast. Relocating half or a third of your fish to a different area is a cheap and relatively easy way to fight that foam.

The Number of Meals Per Day

If you decided that an excessive amount of fish waste in your pond is the main problem, but you don’t have anywhere else to place them another way you can regulate the output of your fish is to simply reduce the number of meals you give them a day.

Reducing the amount of meals could also save you money in the long run! So if you’re currently feeding your fish three to two times a day, and you don’t think the health of your fish would suffer from one less meal time, go ahead and make the cut!

Another useful tip to prevent overfeeding is don’t give your fish more food than they will be able to eat within five minutes. If five minutes passed and you still have a few piles of fish food floating on the surface, you are overfeeding your pets.

Try Anti-Foam Products

Nutrient-Eating bacteria are super helpful in breaking down the build up of organic materials that are causing your pond, fountain, or waterfall to foam. If you decide that this is the way to go, but don’t know where to start looking, don’t sweat it. We did some research for you and here are five products that are known for their efficiency.

1. KoriWorx Defoamer-32 oz- Removes Foam from Decorative and Ornamental Ponds, Safe for Koi: My personal favorite thing about this product is that it is completely safe for all pets, from those with no legs to those with four legs. Based on my research, this defoamer works immediately, with the effects lasting for several weeks, opposed to other products that lasted only 24 hours.

On the other hand, some users of this product have encountered a bit of a slimy residue left over from the product that had a cloudy effect on the pond, so keep that in mind in case you run into similar issues.

Here’s where you can find it on Amazon (FYI – we may receive commissions at no extra cost to you).

2. Microbe Lift 240055 16-Ounce Pond Defoamer Dfoam16: This product also has a reputation for being incredibly fast-working and perfect for fountains and ponds of all shapes and sizes. If you do decide to go with it, just make sure you check it’s expiration date before applying it to your water feature, as this can cause problems, including killing your fish if you have some stocked.

Here’s where you can find it on Amazon (FYI – we may receive commissions at no extra cost to you).

3. PondCare POND ACCU-CLEAR Pond Water Clarifier 32-Ounce Bottle (142G): This ACCU-CLEAR product can work really well, and help the water in your pond get really clear within a couple of days. If you order online, just keep in mind that the containers for this product tend to get dinged up a bit during shipping. That shouldn’t have any affect on the effectiveness of the product though.

Here’s where you can find it on Amazon (FYI – we may receive commissions at no extra cost to you).

4. KoriWorx Water Clear – Clarifies Decorative and Ornamental Ponds, Safe for Koi – 1 Quart: As you probably noticed when you read the name, this defoamer is produced and distributed by the same company who created the first product on this list. Differently from our product in the number one slot, however, KoriWorx Water Clear uses natural bacteria to cleanse ponds it is applied to.

While I love the idea of all-natural products as much as the next environmentally-aware citizen, this product does have a lower rate of efficacy. In other words, we’d expect the number 1 product above, to be more effective for more people, while this product may work in some cases and not work in other cases.

Here’s where you can find it on Amazon (FYI – we may receive commissions at no extra cost to you).

5. CrystalClear Foam-B-Gone Pond Foam Remover – 1 Gallon Treats Up to 128,000 Gallons: I don’t think this defoamer is quite as common as the others, but it still seems to be an efficient defoamer product with a shelf-life of up to three years. The distinguishing feature of this defoamer is probably the fact that you can likely save some cash on it compared with the other products we already mentioned.

Here’s where you can find it on Amazon (FYI – we may receive commissions at no extra cost to you).

Use Distilled Water

Maybe you don’t want to spend any more money than you need to on solutions like defoamers. Switching to distilled water is a great option for keeping your water fountain or waterfall clear, and it won’t add any additional bacteria or chemicals to your water feature.

Because distilled water contains a significantly smaller amount of minerals, it naturally discourages the build up of nutrients/organic material that feed pests like algae and foam. Switching to distilled may not eliminate your problem completely, but it could certainly help lower the amount of organic material being circulated through your water feature.

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We always wanted a fountain of some kind at our house, but professional installation was just too pricey. So, we decided to make our own little fountain and after learning how, we thought we should share our experiences to help people in our same situation.

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