Please help. We have our new pool up and filled 30' round 4.5 deep so - 24,000 gal? This is our first big pool and I want to start right but the water is brown. We often have a brown tint and after the fire dept flushes the lines we get brown sediment in the bath tub and the kids won't get in - smart kids! I am guessing this is the bown pool problem. After sitting the night we can see sediment in the pool and my husband is vacuuming now. Here are the numbers using PS 234.

FC 5 (7 last night after 1 gal Clorox)
CC 0
TC 5
pH 7.2
Alk 60
Cal 20 (not important with vinal pool?)
Cya 0

Should I add Cyanuric acid now? How much? The directions say not to back flush for two days after adding. The pump pressure is 15 so I think we are alright there. Should I run the pump 24/7 until clear?

Thanks in advance for your direction which I have found very helpful thus far.
Dianna