I don't know much about this, but what is the point of
putting it
through the tank instead of straight into the bowl?

CY: Might be clogged rim holes, where the water goes into
the bowl.

If there are, he should do that, but he didn't say anything
about
that.

CY: Which is why we suggested the bucket test.

Also, be sure to add acid to water and not add water to
acid.

This used to confuse me but when you at water to acid,
there
is loads
of acid and only a little water. Any reaction, even just
bubbling,
has a high concentration of acid.

CY: Wrong.

You mean, Right, plus the rest of what you wrote. You said
the same
thing I did.

CY: Still wrong. The problem isn't concentration. It's
stratification. The problem is water floating on top of the
acid while reacting.

Concentrated sulphuric acid is a bit viscous
(gloopy) and heavier than water. Pouring water onto the top
of the acid has been known to layer the water on top of the
acid, which can created a thermal reaction, and splatter.
Also, good to use a stirring stick while pouring, so as to
get a more instant mix.

CY: Layer on top -- stratifying.