Koi food
formulations.

§01 — Formulation categories.

Commercial koi and pond-fish foods are sold in formulation categories that correspond to the dietary goal stated on the packaging. Four categories dominate the market:

• Staple — general daily diet at warm-weather temperatures.
• Growth — higher protein content marketed for rapid size development.
• Colour-enhancing — staple-equivalent base with added pigments marketed for colour intensity.
• Wheat-germ — lower-protein, easier-digestion formulation marketed for cool-water feeding.

This article describes how each category is positioned by the manufacturer in the printed packaging copy. It does not advise on feeding schedules or quantities, which are stated per-product on the bag.

§02 — Staple.

Staple-grade pond fish food is typically positioned for water temperatures above approximately 65 °F (18 °C), the threshold manufacturers commonly cite as the lower edge of the active feeding range. Staple formulations contain mid-range protein (28–32 percent crude protein in published guaranteed analyses) and a complete balance of fish-derived and plant-derived ingredients.

§03 — Growth.

Growth formulations carry higher published protein content — commonly 38 to 45 percent crude protein, with elevated crude fat compared to staple. Manufacturer literature positions growth foods for younger fish or for keepers prioritising size development; guaranteed analyses typically appear on the bag.

§04 — Colour-enhancing.

Colour-enhancing pellets contain natural or synthetic pigments listed on the ingredient panel. The most commonly named ingredients are astaxanthin and spirulina, both red/orange-spectrum pigments. Astaxanthin is sold to manufacturers as a synthetic ingredient and is also extracted from certain micro-algae; manufacturers state the source on the bag.

Colour-enhancing pellets are otherwise nutritionally similar to the same brand's staple pellets — the pigment additive is the distinguishing factor.

§05 — Wheat-germ.

Wheat-germ-based formulations carry lower published protein content and higher carbohydrate content than staple, marketed by manufacturers for water temperatures below approximately 65 °F (18 °C). Packaging typically specifies a recommended water- temperature range and notes that lipid digestion at lower temperatures is the basis for the formulation difference.

§06 — Pellet form.

Pellet diameter is published on every commercial pond fish food. Common sizes:

• Mini — approximately 2 mm, marketed for fish under 4 inches.
• Small / medium — approximately 3 to 5 mm, the most common retail size.
• Large — approximately 6 to 8 mm, marketed for fish over approximately 10 inches.

Floating pellets (the dominant form for koi food) allow the keeper to observe what is consumed and adjust quantity. Sinking pellets exist for catfish and other bottom-feeding species and are also sold under the pond-food category.