In article ,
"jtaylor" wrote:
....
I don't think I did too good a job on the finishing - combination of
misjudging the time to do stuff, and not knowing how to do it anyway.

So I think I would like to paint the top of the slab.

Paint is a good idea, but it won't correct the finishing of the concrete
itself.

What should I paint it with?

Many available paints, expoxies, systems. Depends what you want, and
what you want to pay. I've been happy with UGL Drylock floor paint
(latex base) - not their waterproofer (which is for walls) and I have
not used their oil based. White - makes for much more light than the
typical tan/gray/red or bare concrete. Latex Drylock is easy to recoat
in case of damage, has pretty cgood coverage, and does not require added
antislip materials (it's not slippery) or 3 different coatings, as some
"systems" do. Some folks seem very happy with epoxy finishes, some
people have posted horror stories...

What surface prep should I do - in places I think some of it might come away
pretty easily.

Surface prep should be per your paint/coating manufactuer's
instructions. Cure the concrete for at least 30 days, typically, keep
oil off of it before paint to make cleaning before painting a reasonable
job.

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