Rust infiltrating tank!

the metal legs for my lights are rusting... As a result I have a feeling it's leading to a recent problem. Lately I have been noticing rust colored batches on the sand... Almost as if the saltwater was breaking it down. Is that possible? No matter how many water changes, or UV addition made... Or sand cleaning... The problem returns in a matter of hours. 24 hours to see a noticeable amount. How can I safely clean the rust from around the outer edges where the legs are and then how can I replace the metal legs to prevent future problems? Any help would be great

 

are you sure it isn't algae on your sand? there is lots of rust colored algaes that will grow on your sandbed

 

not sure ... but I've cut back on my lights... 3 hours for 150 watt MH... 6 hours for t5HO 50/50s... I've deep cleaned my protein skimmer... cut back on feeding... added UV sterilizer 2 days ago... and still the problem persists... I'll post a photo of the problem

 

Photo of problem

here's what it looks like...

 

that looks like regular diatoms.
you probably have silicates or something.
they should go away on its own.

 

it's been three months... added a silicate remover... nothing... the only thing that hasn't been fixed... those stupid metal legs leaking rust into the tank. Even if it wasn't it... can saltwater break down the rust into fine particles? Any suggestions on how to replace the legs?

 

Yes salt water can breakdown metal. The legs should be attached with screws somewhere. You may need to remove the housing which should be attached with screws also. A picture of your light fixture would be helpful.

 

definitely not rust. Its diatoms.

What brand light do you have that has metal legs? You could take the light off wire brush it, spray it with rustoleum rusty metal primer, and then top coat it with rustoleum and you should be good to go.

 

here's what the lights look like

48' Metal Halide T5 HO Aquarium Light 150 HQI Moon NEW! - eBay (item 180523376487 end time Jul-07-10 22:00:28 PDT)

This is the light set that I have.
The legs do have screws... I can follow the above post's instructions to safeguard them from future rusting?
I'm surprised though it can still be diatoms. My tank is two years old... with no such problems before.
Any suggestions on how to SAFELY remove the rust on the outer edges of the tank where the legs were sitting? I don't want harsh chemicals to get in the tank but it may prove to be impossible...
Thanks!
Ryan

 

Rustoleum paint to protect the legs and fixture.
You could try vinegar on a rag.