We recently acquired a nice (used) barrel, which we'd like to use with
our RO/DI system, and for mixing salt. The question is, I'm not enough
of a chemist to know what steps we need to take to get it clean enough
that it won't impact the water quality in our tanks.

This barrel originally contained an anticorrosive ("antiscale")
solution. The label lists NaOH and NaNO3. Well, it specifically says
sodium hydroxide and sodium nitrite. I can never remember whether
nitrite is 2 or 3. Anyway. We've rinsed it with copious quantities of
tap water (many many gallons). The hazard label on the container lists
all 0s except for a "2" in the health quadrant. Basically, it's pretty
inoccuous ... for *US*. Whether it's inoccuous to fish or not is
anybody's guess!

I wonder if anyone has an idea what more we can do to make it safe for
our intended use?

TIA
~vicki~

=^..^=
.... the problem with people these days is that
they've forgotten we're really just animals.