metal contamination in tank
 

I was gust wondering if someone knows the effect ore experienced galvanised steel in a reef tank.

reason for asking is because I found a big galvanised bolt in my sump.

the bolt is not so galvanised any more (in fact it is one bunch of rust) but it once was a bolt.

it most have bin added by my little son sneaking in the filter room, and as the bold rolled underneath my skimmer, I had no knowledge of it beighn in my tank system.

as I have bin battling / recovering from some tank problems (algae and corals turning brown )

the bolt must have bin in the tank for at least 1 year, as also some corals where turning brown (thy are recovering)


as I improved my entire maintenance, I don't know if the improvements are duo to the changes I made ore duo to removing the bolt



did anyone had a metal contamination, and what did it do ?

eeeeeek......having a rusty bolt in the sump for potentially that long cant be good.....good thing you found it....

I'm glad I found it, but was gust wondering what it did, as we all dont want it in, it gust wonders me, based on what dont we want it in.


lets hope some others pitch in to find out.

so we dont want it in, but why, what douse it do ?

If was big enough, it might leech Fe+ into the tank, perhpas fueling algae, or at least acting as a catalyst if you've got enough other nutrients. However, in as much volume as you have, I wouldn't give it much concern. As I mentioned when you were over, the small infrequent water changes are probably worse than a bolt. Now that you are doing bigger changes more often, that is probably contributing the better health you're seeing.

It's not the Ferrite or Ferritic oxide that I would be most concerned about but the level of Zinc which formed the galvanized coating, here is an short description of the effect of Zinc in a marine tank:

"Zinc:

Zinc is a necessary element for marine organisms. Zinc concentrations of 0.1ppm to 1 ppm cause lowered growth rates in zooxanthellae. A concentration of 0.1 ppm reduces fertilization in the Faviidae family of corals. Natural levels should be maintained, as it is essential for photosynthesis and for the formation of calcium carbonate by corals.

Some crustaceans can regulate the amount of Zinc intake but at high levels this ability is lost, thereby allowing toxic accumulation. As with many heavy metals, the toxicity of Zinc on invertebrates is increased with decreased salinity.

Maintaining natural levels of Zinc is recommended in your system, which can be achieved through regular water changes using a good quality salt mix."

i'd like to believe the biggest problem it would cause is an increase in algae growth, the Fe being a fertilizer.

but knowing it was sitting in there for so long, i'd probably run some polyfilter along with your regular maintenance for a while.

interesting this topic came up...
i just "lost" a razor blade in my 180 the other day.

that being said i'm going to go out and get a telescoping magnet to probe the tank.

maybe it should be a new must have tool for the reefer!

sethis could be interesting (Zinc concentrations of 0.1ppm to 1 ppm cause lowered growth rates in zooxanthellae) as I have some corals that did not do anything.

I know when I worked with bolds last year, and the growth reduction could be with 2 months tollarance related to this.

as the bolt is out now, and I'm inproving maintanance, I do se improvements.

Are you sure the bolt was galvanized? Or was it shiney? As in cadmium plating

galvanised, as I never both the plated once, always galvanised.

i know it must have bin a year ago, becouse my filter room is right naxt to the front door, and I made a deck in the front a year ago

I must hd my door open to the filter room when working on the deck, and the little bugger went to explore.

again out of interest, and gust to learn, what would be the effect on the metals based on cadmium plating ?