How strong should your ants’ sugar water be?

How we calculate

• Amount to add (g) = strength × water ÷ (sugar content − strength). Sugar content: 100% for sugar, 82% for honey, 66% for maple syrup. Strength: 25%, 33% or 50%, by weight (1 mL of water = 1 g). Rounded to 0.1 g below 10 g, otherwise to the gram.
• Teaspoons = grams ÷ 4.2 (sugar), ÷ 7 (honey) or ÷ 6.7 (maple syrup), rounded to the half teaspoon, at least 0.5. For honey and syrup: volume = grams ÷ 1.42 (honey) or ÷ 1.32 (syrup).
• Mix you get (mL) = water + 0.62 mL per gram of dissolved sugar (or + the volume of honey or syrup), rounded.
• Workers counted = your worker count up to 300; above that, 300 × (workers ÷ 300)^0.75, because big colonies drink less per worker.
• Consumption = 2 drops a week per 25 workers counted, rounded; 1 drop ≈ 0.05 mL.

Example

White sugar at 33%, 50 mL of water, 100 workers. Sugar = (1/3 × 50) ÷ (1 − 1/3) = 25 g, about 6 level teaspoons (25 ÷ 4.2). Mix = 50 + 25 × 0.62 = ≈ 66 mL. The colony drinks 2 × 100 ÷ 25 = 8 drops, so ≈ 0.4 mL / week: the mix lasts well over 2 weeks, so keep it in the fridge for 1–2 weeks at most.

Sources: common keeping practice. These are guidelines: make small batches and throw the mix away as soon as it turns cloudy.

Frequently asked questions

What strength of sugar water for ants?

Most keepers use 1 part sugar to 2–3 parts water, i.e. 25–33% by weight. Above 50% the mix gets too thick.

Can I use honey?

Yes. Honey is about 82% sugars, so you need a little more of it than white sugar for the same strength.

How long does sugar water keep?

1–2 weeks in the fridge. Replace the cotton or feeder every 2–4 days.

How much does a colony drink?

Very little: about 8 drops a week (0.4 mL) for 100 workers, based on the ant calculator.