Recently, we shared an article about Koi fish feeding throughout different seasons, and after that, we received so many questions about what to feed koi fish and what not.
At Zen Aquarium, we have been helping customers feed their Koi properly for over 15 years. We know exactly which foods work best in Australian conditions and which ones cause problems. Today, we will share everything about feeding koi fish the right way.
Whether you just bought koi fish for sale from us or are planning to get new fish, understanding proper nutrition is mandatory for healthy fish that live long and look beautiful.
What Do Koi Fish Actually Need in Their Diet?
Koi fish are omnivores, and in natural ponds, they eat insects, small fish, plants, seeds, and anything that falls into the water. Your job is to copy this varied diet with good commercial food and some natural treats.
Different age koi need different nutrition levels!
Young koi under 1 year need 50-65% protein because they grow really fast. Adult koi over 3 years need 32-38% protein in summer and 25-30% in cooler months.
Protein should come from fish meal, shrimp meal, and spirulina. Avoid foods where plant protein is the main ingredient because Koi cannot digest it properly.
Carbohydrates should be 10-20% maximum. Good sources include wheat germ, rice bran, and corn. Too many carbohydrates cause digestive problems and make your water dirty.
Fats need to be 5-10% of the diet. Fish oil, krill oil, and linseed oil are good fat sources. During winter, you should reduce fat because koi metabolism slows down.
Best Commercial Koi Food Brands That Actually Work
We have tested many brands over our 15 years of helping customers who buy fish aquarium setups. Here are the ones that consistently work well.
Saki Hikari is the best koi food available. This Japanese food contains special probiotics that improve digestion and reduce waste. Customers report better growth, cleaner water, and brighter fish colours. It costs more but delivers real results.
Hikari Standard is cheaper than Saki Hikari but is still of good quality. The pellets float well, and most koi eat them eagerly. Good option for budget-conscious pond owners.
Blue Ridge Koi Food gets good results for growth and colour. Their Platinum Pro line is used by professional breeders. Reasonable pricing for the quality you get.
Microbe-Lift Legacy contains advanced probiotics like Saki Hikari. Their Variety Mix combines four different formulas in one pellet. Good all-around nutrition for koi fish for sale in our store.
Never buy the cheapest food available because poor quality food creates more waste, causes health problems, and actually costs more long-term through fish losses and water quality issues.
Feeding Schedule Based on Water Temperature
Water temperature controls how much and when to feed your Koi. This is not optional - feeding wrong amounts at wrong temperatures kills fish.
Below 5°C - Stop feeding completely. Koi cannot digest food when the water is this cold. Undigested food rots in their stomach and kills them.
5-10°C - Feed wheat germ food 2-3 times weekly only during the warmest part of the day, between 10 am-2 pm. Watch fish carefully for any signs that they cannot digest the food.
10-15°C - Feed wheat germ food once or twice daily. Start very slowly and increase gradually as the water warms up.
15-20°C - Begin transitioning to higher protein summer food. Feed twice daily and monitor fish activity levels.
20-30°C - This is prime feeding season. Feed high-protein food 2-4 times daily. Koi grow fastest during this temperature range.
Above 30°C - Reduce feeding to twice daily maximum. Very hot water stresses fish and reduces their appetite.
Many customers who buy fish aquarium setups make the mistake of feeding the same amount year-round. This approach kills fish or makes them sick.
Natural Foods You May Give to Koi Fish In NSW
While we have already discussed the commercial food brands that are safe and trusted for koi fish, here we will be sharing the natural food that you may give to your koi fish, but of course, in a safe amount.
Vegetables: Lettuce, garlic, broccoli, cooked sweet potato, zucchini, and carrots have good vitamins in them. (Just peel the skins of these vegetables since they're difficult for your kois to digest.)
Fruits may be given occasionally: Watermelon, oranges, berries, and melons. (Don't overfeed fruits since sugar content is high.)
Protein foods: Cooked shrimp, earthworms, and brine shrimp. (Never give wild-caught insects or fish since they harbour parasites that infest your koi.)
Give natural foods sparingly. They are treats, not diet staples. Too much natural food disrupts nutrition and leads to digestive issues.
Foods That Will Kill or Harm Your Koi Fish In NSW & ACT
Certain foods are lethal for Koi and can inflict serious health issues or death.
Bread, pasta, rice, and corn are high-carb foods that Koi do not digest well. These foods result in bloating, swim bladder issues, and intestinal obstructions.
Milk and cheese are poisonous to Koi. Lactose is not digestible by fish, and these foods result in acute digestive distress.
Processed foods for human consumption carry salt, sugar, and preservatives that kill koi fish. Never feed chips, crackers, or such foods.
Wild-caught animals from your yard can be diseased or parasite-ridden, so just never feed wild insects, frogs, or tiny fish to your koi fish.
Zen Aquarium Helps You Feed Your Koi Properly
At Zen Aquarium, we provide ongoing feeding advice for all customers who buy fish aquarium equipment from us. Our 15+ years of experience help you avoid common feeding mistakes that kill or sicken koi.
We stock all the premium food brands that work well in Australian conditions. When you buy koi fish for sale from us, we provide detailed feeding schedules based on your local climate and pond setup.
Our customers get access to specialised foods for different seasons, ages, and health conditions. We help you choose the right food for your specific koi and pond situation.
Whether you need feeding advice for new fish or help solving feeding problems with existing koi, we provide expert guidance. Call us at 0478 757 332 or email info@zenaquariumau.com for personalised feeding recommendations.
Our physical store opens only on SUNDAY at Paddy's Market, Flemington, from 7 am to 3:30 pm. You can find us at Building D, 250-318 Parramatta Road, Enter Via Potts St or Austin Avenue, Homebush West, NSW, 2140.