> I don't have a good answer to that, but I would probably be trying a
> chemical attack, like phosphoric acid or CLR (which contains
> phosphoric and
> oxalic acids as I recall).
>
> I've always seen Muratic acid used to clean brick/cement ???? wonder if
> that would cut it
I've got rust stains on the plaster of my pool, where vandals threw in
iron/steel objects (like the lock off my stolen bicycle). Muriatic doesn't
seem to touch them.
But Home Depot sells the Zep equivalent to CLR by the gallon. Not nearly as
cheap as Muriatic, but not all that expensive either.
Randall
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