Things are turning brown in my "bulletproof" tank.. good or bad?

My husband and I just bought a 110 gallon saltwater tank that has been established for about 6months (Garf bulletproof theory tank). It took 5 hours to transport it home. We left the plenum in the tank during transport but scooped as much sand out as possible and put it into tubs for transport. When we got back home, we put the live sand back on top the plenum, filled it with saltwater, and stuck a powerhead to a tube that reached under the plenum to sucked water from the bottom space----in theory pulling all the debris in the water back into the live sand where it should be.

There is only sand and water in the tank. After 2 days we tested the water and found 0 nitrates, nitrites, ammonia, phosphates. The pH was 7.4.

We plan to put dry base rock in tonight--let that sit for a week and buy a few choice pieces of live rock--let that sit for a few months. Today we noticed that we have a brown film on our sand and glass.

Opinions about what we're doing? Is that brown algae good or bad?

Thanks so much!
~Pepper

 

Diatoms?

 

The brown dust like stuff is diatoms. Usually come after a cycle or if you add anything plastic to the system as they feed of the silicates that leech from new plastic. They are nothing to worry about and will go away when they use up the available silicates.

 

Okay, awesome! Thanks guys!