Rust colored covering in new Reef

[::pete::]

I recently started a reef aquarium ( approx. 2 weeks ago). I changed the original bulb to a blue buld which darkend the appearance of the tank. It has live sand and rock as well as a blue back, the test showed that everything is at or right about where it should be. Now for the question I am needing help with. I started noticing a growth on the top of the rocks that was visible due to a color variation and when I shined a flash light on it, it didnt look right so I switched the bulb back to a white fluorescent. The rock and sand have a rust colored covering and I am wondering what to do? or is this bad? I have a protein skimmer running at this time which seems to be working fine.

Thanks Pete

[MikeP]

Definitely look like diatoms to me. They should pass of their own accord in a new tank.

[::pete::]

Water was tap with instant ocean added. As for the light it is just the light that came with the tank. The blue light I switched to is 30watt 100% actinic 03 blue. Hope this helps.

[djdubdub]

Pete...

I'm pretty new to this too... I had the same thing after starting my tank w/ tap water... I was told the phosphate level in the tap water will cause this...

It will go away on it's own... If it gets too "unsightly", I used S.A.T. to help remove it... But letting nature take it's course is best...

Best thing to do is to use R.O or D.I. water...

Good luck...

[utmachete]

I agree with justletmein you should get an R/O unit. Champion lighting has specials on Kent R/O units I think there are bare-bones ones for $80 that would be good enough but I would at least go with the three stage.
http://www.championlighting.com/e/en.../rofilter.html
You can also get some at Home depot that are really good and I think they are only about $150.
Life is so much simpler with an R/O unit, and your tank should quickly outgrow those cyano probs. Make sure you have enough light though?

[::pete::]

Before I delete the topic I 'd like to thank everone for their help... Thanks