Koi food label. Understanding a koi food label

As consumers, we’ve never had access to as much information abut our purchases than we do today. Our biggest problem in this ‘Information Age’ is that we just don’t have the time to take it all in. This means we have to be more selective about what we choose to read, and whether it will benefit us or not. As dedicated koi keepers, we are naturally hungry for any information that will help us understand and develop our knowledge about every aspect of our hobby. There’s a lot of information on specific products, but especially koi foods, and just as a wine connoisseur will make it their business to scrutinise a wine label, we too can learn a lot from koi food labels.

There is a hierarchy of factors that we would routinely look for in a food. Those at the top of our list will include the brand, the price and soon after, the protein level and so on. Manufacturers go to a lot of trouble to provide accurate and detailed information on their products and there’s lots we can learn from a label, using it to make the best choice for our koi and ourselves.

Let’s take a look at a label.

Statutory box.

Every koi food label must, by law, display a box in which is declared:

  • The product description
  • How to use the food
  • Ingredients
  • Analysis
  • Contact information
  • Date and batch references


Within these guidelines, there is some degree of flexibility, giving manufacturers the option to include additional information.

1. Product description. A complete food for koi. Complete means that no other food is required to supplement this diet to provide koi with all the nutrition they require.

2. Feeding Guide. There is a legal requirement to describe how the product is to be used safely and efficiently. The additional advice about removing uneaten food is not a legal requirement, but is added as an additional precaution, realising that uneaten food will threaten water quality.

3. Ingredients. These are listed in descending order, with the most abundant ingredient first. This is your opportunity to explore the food in more detail, ‘un packing’ the ingredients to establish what protein sources may contribute to the 43% protein in the diet. In this case, fish meal is the clear main protein source. Other vegetable sources of protein for our omnivorous koi are found in the subsequent ingredients: maize gluten, maize and wheatgerm. Towards the end of the ingredients list, the smaller ‘functional’ ingredients are found. Spirulina, astaxanthin and canthaxanthin are included for colour enhancement. NishiClay, propolis and NishiGuard are added as health supplements. Fish oil is included as a high quality lipid source, with other lipids also entering the diet via other ingredients such as fishmeal.

4. Vitamins per Kg. Only vitamins A, D and E need to be declared, even though as a complete diet, the food will of course contain all the vitamins. Some vitamins are measured in international units (iu) while Vitamin E is measured in mg. A defining criteria between foods is a high level of Vitamin C, something that different manufacturers differ on whether they choose to declare it or not.

5. Analysis. There are countless ways in which a diet can be analysed, but legislation dictates that 5 criteria are declared.

Protein is the single greatest constituent in this diet. It would not be in a lower protein ‘winter’ diet. Ash at 8.8% is a measure of the inorganic or mineral content of the food. This is probably one of the highest ash levels for a Nishikoi food on account of the high fishmeal content – bringing with it an inevitable contribution of minerals. Fibre is a measure of the complex carbohydrate in the diet. In a natural diet, this would be much higher, but the demand for low-waste koi foods means that the fibre content is kept low. Moisture at 7% means that the food will remain stable, with a prolonged shelf-life. A higher moisture content will speed up the food’s deterioration. This is why a food should be resealed once opened in an airtight container.

Where’s the missing 34.2%?

By adding together the declared analysis, we reach 65.8% – so where’s the other 34.2%? This is largely accounted for by carbohydrate. Legislation does not require a carbohydrate declaration. Yet carbohydrate to koi is so vitally important, with them gaining a significant proportion of their energy from it. In fact, in some lower protein formulations (such as Wheatgerm foods), the carbohydrate element of the diet may make up the majority of the food and yet it can remain undeclared on the label.

6. Batch Number and Vitamin Levels. Look on the pack for the best before date and check whether it is sufficiently long for you to use your food. After this date, the food does not become unfit for consumption, but the vitamin content is likely to have dropped below the declared levels.

7. Manufacturer’s contact details are required so that in the event of a query, the manufacturer can be contacted.

8. Net Weight. This is a declaration of the weight of food, excluding the weight of the packaging. The density of koi food caries between different brands so that different weights will fit into packs of the same volume. The only way to really verify the weight of food you are buying is to check the declared weight (and not the pack size).

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