FAQs
Have Questions? We’ve Got Answers.
Below you’ll find some of the most common questions we get about koi ponds—from construction tips to water quality and fish care. But if you want more detailed info or have a specific situation, our chatbot is always available to help you dive deeper—just click and ask!
How deep should a koi pond be?
Target 3 – 4 ft (1 – 1.2 m); colder climates or jumbo koi benefit from 4 – 5 ft for freeze-proofing and predator safety.
Ideal pond volume per adult koi?
Plan 250 – 500 gal (950 – 1 900 L) per fish. A quick rule of thumb is “1 inch of koi per 10 gal,” but bigger is always better as they grow
Best construction material—liner or concrete?
EPDM liner is DIY-friendly, flexible, and easier to patch; concrete (with rebar and a waterproof render) is bullet-proof but costs more up-front and needs expert sealing.
How do I integrate a bog/wetland filter at the build stage?
Dedicate 10–20 % of total pond surface to the bog, feed it via a bottom-up manifold, and return water over a weir. Plants + gravel = powerhouse bio- & mechanical filtration with near-zero maintenance.
Pond shape for best circulation?
Gentle curves (kidney/oval) or straight rectangles with rounded corners keep debris moving. Avoid dead-end coves; aim every return jet to create one slow “racetrack” current.
Bottom drains, skimmers & return-jet layout?
Place 3-in. aerated bottom drains every 12-14 ft, centered in a shallow dish-shaped floor; partner each drain with a skimmer on the opposite wall to pull surface flow the same direction.
Which filter style suits a mid-size backyard pond?
Bog ≈ lowest upkeep; moving-bed or bead ≈ compact & high-flow; pressurized canister ≈ easiest retrofit. Match flow so the entire pond turns over at least once per hour.
How often do I test water (pH, ammonia, nitrite, KH)?
Weekly for mature ponds; every other day after adding fish or meds. Keep ammonia & nitrite at 0 ppm, pH 7.0 – 8.6, KH > 80 ppm for buffer.
Fastest green-water cure that’s koi-safe?
Size a UV clarifier at 10 W per 1 000 gal; expect clear water in 3–7 days. Shade & plant cover help long-term
Do I need the UV running all year?
Run continuously in warm months; in winter shut it off once temps drop < 50 °F (10 °C) to save energy and extend bulb life.
Pump & waterfall sizing for O₂ vs. power draw?
Move full pond volume hourly (e.g., 3 000 gal pond → 3 000 GPH pump). Match head height and add an air diffuser at ≥ 1 cfm per 1 000 gal for cheap oxygen
How many koi can I keep?
Stick to the volume rule above; over-stocking stresses bio-filters and fish.
Quarantine protocol for new arrivals?
4-week minimum in a heated (70 °F/21 °C) 300+ gal tank, separate filtration, daily parameter checks, preventive parasite scrape & salt dip.
Key symptoms of parasites or bacterial infection?
Flash scratching, red streaks, excess mucus, fin clamping, or ulcers. Treat after a scrape/skin biopsy confirms culprit (e.g., Fluke-M for flukes, oxolinic-acid or medicated food for bacterial ulcers).
Safe temperature swing when moving fish?
Limit ΔT to ≤ 3 °C (5 °F); float bags 15 min, then drip-acclimate 30 min before release.
Filter clean-out & water-change schedule?
Rinse mechanical pads weekly; back-wash bead filters bi-weekly; change 10-20 % water weekly (more in summer or during ammonia spikes).
Sludge removal without draining?
Vacuum pond bottom seasonally or dose beneficial-bacteria “muck tablets” monthly; a correctly sloped floor + bottom drains prevents most buildup.
Best koi diet across seasons?
Spring/Fall (< 68 °F/20 °C): wheat-germ or 30 % protein; Summer (> 68 °F): 35–40 % protein growth pellets 1-3× day; Winter (< 50 °F/10 °C): stop feeding or offer sparse low-protein wheat-germ.
Keeping the pond ice-free in harsh winters?
Run a shallow-placed air diffuser plus a 200-300 W floating de-icer to maintain a 6–8 in. opening for gas exchange. Turn off deep aeration to avoid super-cooling.
Predator-proofing tips (herons, raccoons, etc.)?
3–4 ft depth with vertical walls, tight pond-netting in migration season, motion-spray deterrents, and a heron decoy positioned away from the pond edge.