Your assumption is typical of many new aquarists.
Your reasoning is logical and if it wasn't for a small detail, it would be
the perfect water to use.
The only small detail that you are not considering is that in the ocean
there are, other than contaminants, a whole spectrum of bacteria and
microorganisms that are dangerous to aquarium fish. In the ocean, fish get
a fresh pool of water every nanosecond, in the aquarium your fish will be
stuck with it for weeks or months.
In the wild fish are able to coupe with these microorganisms but in your
aquarium they won't.
There is also the larvae and juveniles of dangerous species that could
create havoc in your tank, copepods of all sorts just to mention an example.
I wouldn't use ocean water if I don't UV-filter this water many times before
adding it.
Consider my position and read about it from other sources.


"KurtG" wrote in message
...

I'm currently mixing salt water for my tank, but as I do this, i gaze out
my window at the ocean and wonder. Wouldn't real Ocean water work better?
It would have all the ions, minerals, etc, but it may have some unwanted
bacteria.

I live close to the atlantic. I've heard of fish stores in Santa Clara
that send a truck to the ocean every few weeks to collect ocean water.

Any ideas?

--Kurt