Moersch HCA Washaid is a powder wash aid for film and paper, making 1 litre of stock.
What it is for
It does what other wash aids do: chemically displaces residual fixer from the emulsion, the cause of prints yellowing over the years. The maker adds a useful note on regimes: the normal 1+9 dilution keeps in an open tray for several days, while the economical 1+19 is better mixed fresh for each printing session.
How to dilute it
The working dilution is від 1+9 до 1+19.
Treatment time for paper at 1+9 is three minutes.
Storage
Sealed powder keeps for years; mixed solution keeps far less well, so mix what you will use. Dissolve at the stated temperature and in the stated order — getting the order of components wrong ruins a developer more reliably than any timing mistake.
How it compares
A cheaper alternative to Kodak Hypo Clearing Agent and very close in substance. Powder takes less space and keeps longer than a liquid.
