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Frustration sets in when...


Dec 22, 2004
I replaced all my return hoses with pvc plumbing this week and Today I set it up pumping in a rubbermaid full of tapwater to rinse out the manufacturing dust. This was apparently a very bad choice, since I took the system out of the water and see some mild orange deposits in the drilled PVC holes. My copper test doesn't show anything remarkable, so I assume its all good old iron oxide.

I brushed it out as well as I could, and set it rinsing again in what RO water I had left from filling the tank. I should have done the initial rinse in RO water, but its about a half hour drive to wal mart and I guess I was just a little lazy.

Is all lost? Am I going to have to put out for a new pump to protect my system from the iron?

I know copper is a no-no, however I have never heard anything about Iron being leathal, but that by no means, means I am correct.
Copper is the most lethal metal for cephs, but they're supposed to avoid all heavy metals.

I don't understand how you could have iron oxide wth pvc pipes and your pump. Perhaps it's something else. Just my opinion - I think you'd be OK using tap water for rinsing as long as you finished by using the RO water.

We need a tank chemistry expert to answer this one.

If this is a short run, it sounds like you have some sort of a chemical reaction going on...doesn't necessarily mean a metal problem. PVC can change colours due to formaldehydes, etc too... maybe even the chlorine.
The rust is from my tapwater. I didn't see it because the rubbermaid I rinsed the plumbing in had a dark color. I filled my bathtub partway and, sure enough, brown tint to the water.

There are two places where I have a little bit of brown-staining on my return plumbing. The first is where part of the sump-to-pump PVC which partially protrudes outside the tank, there's a waterline mark. The other is at the pvc spraybar where water returns to the main tank, the holes are rimmed with a little bit of color.

Can I brush these off, maybe with a bit of bleach (I am not a chemist!) and then let the pump rinse itself in some purified water for a few hours?

Please forgive me, since my last experience I have been a little paranoid!

maybe im very naive but i wouldnt see iron oxide as a major problem as this is what anti phosphate media is usually isnt it?

As long as its not distorting the tank water colour i'd imagine??
When I broke down my reef tank, I found the PVC that the rock was attached to, particularly the parts that were in the sandbed, were covered with deposits of iron oxide. Sources for iron are many especially in lighting set-ups and metal hose clamps. I did not have any problems with iron in the reef, including mollusks like snails, limpets, clams and echinoderms such as brittlestars etc. I don't think you have anything to be concerned with. However, people should be aware to use nylon hose clamps and nylon bolts etc., whenever possible.

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