Strange Question regarding brass fittings

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Aquarium Advice Freak
Jul 10, 2004
I've never thought twice about this, until today.

When I setup my sump, I had to use a brass fitting to connect the MAG drive pump (outlet side) to my plumbing. The brass fitting is exposed to the water in the sump.

Now I am wondering if the brass fitting is leaching copper into my tank. It's been in use for about 2 months.

Should I be concerned? If so, what should I do?

Brass is composed of appx 70%copper and 30%zinc. I would say that if the fitting is in direct contact with the water it is completely possible that you will have leaching. If you have a copper test kit you should test but I would definitely be on the safe side and replace it with stainless or something else that does not contain copper.
I can't believe I overlooked this tiny detail. I'm going to pickup a copper test tomorrow.

I assume if the copper test reads positive I should forget about ever keeping any type of invert or coral in this tank?
Maybe yes maybe no. Chemi pure says on the package that it pulls copper out of the tank. I have a qt that I used coppersafe in and wanted to use for a tank. The lfs said that some forms of copper dissipate after a length of time and become inactive somehow. I have had a sebae anemone, a few corals, snails and crabs in it for several months now and they are doing great. However, I did empty the tank, leave it empty for a month, bought new substrate, and new rock. Only the tank itself and the filter were reused after the coppersafe. It's possible that the zinc and the process that forms brass may have kept it from leaching copper so far, but continued exposure to salt water cannot be good for it. Do the test and get the new fitting and hope for the best.
The results are in from the copper test...

It only shows a trace of copper. The hard part to tell is the exact amount. The test reads from 0 -> 0.3 -> 0.5 -> 1.0 -> 2.0

My test does not read dead on 0, but it's well below the 0.3 mark. I tested it 3 different times and got the same result each time.

I've heard there are trace amounts of copper in salt mixture so maybe this is what the test is picking up?

I had the LFS order me a fitting to replace the brass fitting. Should be in tomorrow/Friday. I'm also going to run some Poly Filter for the next month and see what it removes. I've read if you run Poly Filter it will turn blue if it's removing copper.

Guess I thought the worst and got the best. Still worried about the trace amounts showing up but I could just be over reacting.

Thanks for all the advice!
My salt doesn't show have enough copper to show up on the test kits. And that's the second time I've seen Polyfilter on this forum. What is it?
Well... I could just be look at it fearing the worst. It does not read anywhere near 0.3 (which I know is lethal to inverts) but it does not read dead on 0. Again, I think it's all in the way people look/see color charts.

I think (knock on wood) I am safe.

As for the Poly Filter... I don't know first hand but from what I read people that use it sware by it. Removes just about everything from water.

Poly Filter Description: "Chemical filter sponge for removing water impurities such as nitrates, phosphates, silicates, ammonia, copper, and chlorine and parasitic medications after treatment. Turns different colors based on what's be removed."

We're about to find out! :)
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