Koi Pond Filtration
The part you don't see is the part that keeps your koi alive.
A beautiful pond with weak filtration is a slow way to lose koi. Filtration has to be sized to your pond's actual volume and fish load — not fitted with a generic kit. We plan and install mechanical, biological, and UV filtration systems, and we also work on existing ponds that are struggling with green or cloudy water.
How filtration works (4-step):
- Bottom Drain
- Mechanical Filter
- Biological Filter
- UV Clarifier
What's included:
- Filtration sizing based on pond volume and koi load
- Bottom drain and plumbing layout
- Mechanical and biological filter selection and installation
- UV clarifier sizing
- Circulation and turnover planning
- Filtration upgrades for existing, underperforming ponds
"Filtration planning and installation is one of the services we provide independently of full pond construction — if your pond already exists and the water quality isn't right, this is usually where the problem starts."
Common problems this solves:
- Green or cloudy water
- Koi gasping at the surface or showing stress
- A pond that needs constant manual cleaning
- An undersized or poorly placed filter system
Frequently Asked Questions
My pond already exists — can you just fix the filtration?
Yes — filtration upgrades on existing ponds are one of our most common jobs. We assess your current setup and size the right fix.
What causes green water?
Usually an undersized or imbalanced filtration system — not enough biological capacity, or no UV clarifier to control algae.
Do you supply the equipment too?
Yes — you can browse pumps, filters and UV clarifiers directly in our Pond Supplies collection.
How do I know if my current filtration is sized correctly?
A quick way to tell: persistent green/cloudy water or stressed-looking koi despite regular cleaning usually means it's undersized. We can assess it on a site visit.