How much do you need?
A typical vaporizer dose is 2 g per brood box, and most beekeepers treating a full-size colony run 4 g. A 400 g bag is about 200 treatments at 2 g or 100 at 4 g — a season for a hobby yard. The 5 lb bucket (about 2,270 g) is roughly 1,100 treatments at 2 g or 560 at 4 g, and is what most Turbo owners and anyone running 20+ hives buy.
Why EPA-registered matters
Wood bleach and industrial oxalic acid are not labeled for use on bees and are not legal to use as a pesticide. EZ-OX carries the EPA registration, so the label tells you the dose and the timing, and you are covered if anyone asks. We wrote up the differences in which oxalic acid to use for bees.
Dosing and safety
Start with how much oxalic acid per hive for dose, timing and schedule, and how to use a vaporizer safely before your first treatment. The vapor is an irritant: wear a full-face respirator with organic-vapor cartridges, not a dust mask.