Ugly stage? Do I leave it alone?

[Tbone2370]

I am running my first saltwater tank, and I started the process in November. I have been following the cycling process recommended by BRS. I started of with treated Dry Rock (not live), live sand and Dr. Tim's bacteria with one fish from day one. I have had my lights off this entire time, however, the tank is in my office where I have the office lights on from time to time and there is natural light as well.

I only had one fish for 6 weeks as I checked my numbers once a week. After 6 week, ammonia and nitrite was zero and only nitrate was present. According to the process I was following, it was safe to add one fish every 2-3 weeks. I now have three fish and my tank is showing this brown/orange like dust that can be blown off. My nitrates were high so I did a 20% water change last night. I am not sure if this is normal because I have had some people say it is fine but others have said it is cyano and that I need to use chemiclean to get rid of it.

Also, the method I was trying to use by BRS should reduce or eliminate any algae growth but if it doesn't work as intended, and this turns to cyano and then hair algae, is that ok?

 

[Koh23]

Reduce source of natural light... And turn your lights on, then let nature do its thing.....

Poor shot of rock that's 8 month in tank, started dry and sterile, lights from second month on....

Hard to see, purple/violet color of rock

 

[Waters]

I would add a CUC, turn your lights on, and let it mature