Though they both have the same name, there's a difference between ounces, which measure weight, and fluid ounces, which measure volume.
Liquid measuring cups indicate that 1 cup = 8 ounces. But what they really mean is 1 cup of liquid = 8 fluid ounces. For dry measurements, the rules change. Because dry ingredients vary greatly in weight, you can’t rely on the same conversion. For example, 1 cup of all-purpose flour only weighs 4.5 ounces, not 8 ounces and 1 cup of sugar weighs 7.1 ounces.
When making bee syrup, you want the water/sugar ratios to be by weight, not by volume. Sugar is sold by weight, so you just need to consider the weight of the water you are using to get the proper 1:1 or 2:1 ratios we use to feed the bees (1:1 in spring and 2:1 in the fall). In both cases it is better to round the amount of water down to make the syrup a little sweeter than the specified ratio and still get the volume of syrup you want to make.
1:1 spring bee food
18 cups water (that is only 9 pounds)
10 pounds sugar
Makes about 2 gallons 1:1 syrup
(We reduced the water to 9 pounds to get about 2 gallons.)
2:1 fall bee food
9.5 cups water (4.75 pounds)
10 pounds sugar
Makes about 6 quarts 2:1 syrup
(We reduced the water to 4.75 pounds to get about 6 quarts.)
Bring the water to a boil, then stir in the sugar and keep stirring until all of the sugar is dissolved. Place 1 tablespoon of Honey Bee Healthy into your jars then pour in the syrup. Allow to cool before feeding to the bees.