"Wayne Sallee" wrote in message ...
After about 2 years of use, I can't see any
deterioration.

When it is left outside the water and salt crystals
form, then serious deterioration occurs. Tough I
have an aluminum rod that is in the sump in a
position that it is in and out of the water, and yet
it has not deteriorated any that I can see. It is
encrusted with coralline algae, and other encrusting
stuff.

So even the part which is outside of water did not corrode?

Try it with aluminum foil. Stick a piece in your
sump and pull it out, let it sit in your sump, just
outside of the water and let the drops of salt dry.
Give it a few days, and you will see holes in the
aluminum foil. Then stick it back in the water and
leave it submerged. Also at this time ad a fresh
piece of aluminum foil left completely submerged,
and watch what happens. You will see that there will
be no more deterioration.

Interesting...

Why then reef chiller manufacturers use expensive
and very hard to work with titanium instead of using
cheap and easy to work with aluminium ?