Initial set-up

Question
QUESTION: I have a 55 gal. tank I started on Feb. 24.  I have 2 powerheads and a heater only in there now.  I used tap water, Reef Crystals salt and added Prime water conditioner.  My substrate is aragonite sand.  I also added some of the water and substrate material I suctioned out of an existing tank I have.  I have a chromis and a damsel in there, too.  I also added one piece of live rock from my existing tank.  I did not start testing my water for about 2 weeks since I thought it would take that long for the conditioning period to start.  As of last night, I have seen no changes in my water.  The salinity, ammonia, PH and nitrites are all within normal range.  My nitrates are climbing, though.  The tank has developed a brownish film on the glass and my substrate is completely covered in a brown deposit.  My knowledge of saltwater aquariums is probably at an advanced beginner stage.  I just need to know if I have done everything right.  Do you think my tank cycled so fast I missed it?  I'm concerned about the brown deposits also.  

I also need an opinion about equipment.  Do you recommend using a protein skimmer and a hang-on or canister filter?  Some people are telling me that only a protein skimmer is needed.
ANSWER: brown is probably algae. check nitrate level. you need the cannister filter in service now and the skimmer after the tank cycles and you have it stocked.

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QUESTION: Can I have your opinion about the 1st paragraph?  I'm at a loss as to whether my tank has cycled yet or not.

Answer
CYCLING HAS ONLY TO DO WITH AMMONIA AND NITRITE CONTENT REDUCING TO ZERO WHILE NITRATES INCREASE, BECAUSE THATS WHAT THEY TURN INTO. AS FAR AS ALGAE - THEY FEED ON NITRATES SO IT IS A DOUBLE EDGED SWORD. TRY TO RAISE YOUR LIGHT ABOVE THE TANK ABOUT 6 INCHES, SCRAPE THE GLASS AND SIPHON THE SUBSTRATE.