I’m writing about parrotfish. Parrotfish eat algae off of rocks and coral. To get the algae, they chomp off bits of rock and coral and grind them up in their esophagus. The fish then excrete fine sand. A single parrotfish can produce up to 500 kg. of sand in a year.

I want to put that in human terms. 500 kg. of sand would fill so many gallon milk cartons or so many two-liter pop bottles or so many of some other familiar, standard object.

So I need to know how much does a given volume of sand weigh? It can be any volume – a cubic inch, a cubic centimeter, a fluid ounce, a dry ounce – whatever. Give me a number, and I can do the math to get to milk cartons or pop bottles or whatever.

Thanks in advance.