Using 1 quart distilled water,
add 1 oz bottle of A126 Fluorescein green color concentrate
Remove a tubing connector from the manometer and pour fluid in to mid-point level.
Shake to remove air bubbles and slide scale so zero mark is in line with the meniscus of the two fluid columns.
For readings in inches of mercury, fill with (13.6 sp. gr.) triple distilled mercury.