Pond Size
1000 gallons MINIMUM for 4-5 koi. 2000+ gallons for proper colony of 8-10.
Koi grow to 24-36 inches in adulthood. Small ponds = stunted, sick fish.
Filtration
Pond filter rated for 2x your pond volume per hour. Mechanical + biological + UV minimum.
Bottom drain critical — surface skimmers do not reach koi waste at depth.
Water Quality Standards
Same standards as aquariums but at scale. Test ammonia, nitrite, nitrate weekly.
Pond depth: 4 feet minimum for winter survival in cold climates. Shallower ponds freeze solid.
Health Management
Quarantine new koi 4+ weeks. Pond shopping = bringing home parasites and KHV (Koi herpes virus).
Annual prophylactic treatments: dimilin (anchor worms), praziquantel (gill flukes), formalin (ich).
- ✦Cost reality: $5-10 USD per gallon for proper koi pond setup
- ✦Predator protection — netting prevents bird and raccoon attacks
- ✦Source from established breeders, not box stores — quality is night and day