It has been implied on a number of posts that brass is not a good choice for exposure to sea water in a tank, why is this so? Any other metals worth avoiding?
Hi Comaxho,
Brass is an alloy of copper and zinc, both considered heavy metals and toxic to inverts. Bronze is just as bad, an alloy of copper and tin.
The reason is oxidation of the parent materials by saltwater allow them to be introduced into the system. They are hard to remove so they build up to toxic levels in the system. Most metals should be avoided for this reason. Corrosion [oxidation] occurs rapidly with exposure to saltwater and increases the risks of metal oxides entering the system.
Most saltwater aquarist use plastics where ever possible because they are basically inert. Titanium and some types of stainless steel [not all] are saltwater safe.
Remember water is the universal solvent and errode most materials if flow and pressures are right. Grand Canyon in just a few millions years or 12" thick titanium in minutes at 55,000 psi [industrial high pressure water cutter].
I hope this helps.