Koi Pond Results
Inspiration for your koi pond
See how other koi pond owners have designed and maintain their ponds. From traditional fish ponds to modern designs—discover proven methods for clear water.
Koi Pond Solutions
Many people think that koi and plants don't go together.
In reality, the problem almost always lies with the setup, not with the koi themselves.
Read below to find out how to fix this.
Barry's Koi Wall
Thanks to the biofilter towers, my plants are finally thriving, my koi are swimming in clear water, and I’m enjoying a lush, green pond.
Used by Barry
After contacting customer service, he opted for a practical solution: a wall of biofilter crates with loose oxygenating plants and Water lilies behind them.
This allowed him to easily create a powerful plant filter, eliminating the need for a pump and filter system.
Simon van der Velde
Complete your pond kit
Order crates right away, or pick up a sample set to try them out and see if they fit.
Test Set (3 pieces)
Perfect for trying things on and measuring. Stackable and sturdy.
12 crates + growing medium
Simon's Choice: Fill the crates with growing medium for a vertical plant filter. Maximum purification!
Over the past 40 years, I have observed more than 1,000 koi ponds.
From meticulously landscaped show ponds with drum filters to large koi ponds with hardly any plants.What I keep seeing:
—a lot of technology, high fish density, and almost no natural buffering.And that is exactly where the problems arise later on.
Cloudy water. Thread algae. Poor growth. Unstable water parameters and the use of a pond net.
The 3 Most Common Mistakes When Building a Koi Pond
Mistake 1: Too high a stocking density per cubic meter
Many people have too many koi, and they're too big, in too little water.
Many koi ponds start with 5 or 6 small koi and end up with 80-centimeter fish in the same pond.
Result:
- Chronic high levels of ammonium and nitrate pollution
- Chronic floating algae or filamentous algae
- Unstable water levels
- Inhibition of growth
Technology can temporarily mask this, but the biological load remains too high.
A koi pond is not an aquarium that you can “filter out” indefinitely.
Mistake 2: No plants
Many people rely entirely on technology, with no natural buffer
Problem: Drum filter, moving bed, UV, skimmer, but no plants, no substrate, no natural nutrient uptake.
Result:
- Nitrate builds up
- The water remains "chemically clean" but biologically poor
- Faster algal blooms as temperatures rise
- Greater reliance on water changes
Technology removes debris.
But technology does not consume nutrients.
Without biological uptake, the system remains vulnerable.
Tip 3: No hiding places for fish
Many people don't have floating plants, which means the koi have nowhere to hide
Mistake A: Placing plants loose in the pond.
Mistake B: Not using any plants at all.
Koi:
- pull up plants
- eat young shoots
- stirring up the substrate
Result:
- Broken within a few days
- Disappointment
- Then people decide that “plants don’t work with koi”
Plants do work with koi.
But only if you:
- Isolates in a plant filter
- Protects in crates
- Works with floating islands
- Or creates a separate wetland area
Marijke's Deep Solution
The idea of stacking crates on top of each other finally brought peace to my pond. The plants are staying put, and everything is now growing as it should.
Used by Marijke
Herman's "Island Solution"
A hiding spot for my koi, flowers for me, and finally an open pond without a net.
Used by Herman
But he wanted less algae, more oxygen, hiding spots for his koi, and no more netting to keep out the heron.
The solution: a plant island.
The island floats steadily, the koi can’t reach it, and the plants do the work.
Less algae, more relaxation for Herman and his koi, and a beautiful open pond without a net.
Simon van der Velde
Learn more about a plant filter
Different methods for making a plant filter and purifying your water naturally.