Power head rotors exposed to saltwater

Tombones · May 30, 2020

Im not sure this is a chemistry question but do you know what power head rotors are made of and do they leach metals into reef aquariums? They are magnetic and everyone seems to be concerned about magnets in the reef aquarium. Thanks for your time to answer this question.

Randy Holmes-Farley · May 30, 2020

You mean the magnet part? I'm not sure of the exact compositions used, but many folks uses them without apparent issue.

Do you have an issue?

Tombones · May 30, 2020

Yes sometimes high tin, sometimes high iron. Both of these metals in the last two ICP test. I have checked everything in the tank for possible pollution as well as my RODI unit. It had just occurred to me rotors are magnets and many reefers have had problems with seals on magnets breaking and corroding, adding metals to their aquariums. I have used the Triton method for over two years now and I keep having to do water changes anyway because of the accumulation of metals. I guess water changes are necessary for my tank. Bad water out and clean water in.
Thanks for your reply.

Randy Holmes-Farley · May 31, 2020

Tombones said:
Yes sometimes high tin, sometimes high iron. Both of these metals in the last two ICP test. I have checked everything in the tank for possible pollution as well as my RODI unit. It had just occurred to me rotors are magnets and many reefers have had problems with seals on magnets breaking and corroding, adding metals to their aquariums. I have used the Triton method for over two years now and I keep having to do water changes anyway because of the accumulation of metals. I guess water changes are necessary for my tank. Bad water out and clean water in.
Thanks for your reply.

I'm not aware of tin being used in magnets, and elevated tin is very common. How high? if less than 10 ppb, I'd ignore it.

Elevated iron is less common if you are not dosing it, since it readily precipitates and is used by organisms. It generally isn't toxic.