Why won't my pool get clean?

[mohawk]

Well I ran the pool rover tonight and had my son get out his scope. I can't find any pics of algae so I don't know what to look for in the scope. Nothing moved-and it looked like dirt. I took a water sample in today to the local store and they said no green-black-mustard or slime,mold algae. Although I have some cc. I showed nothing(cc) when I ran my own test. This is really baffling me. I read else where on the web that some suggests using sodium bromide or ammonium sulfate along with chlorine. Any thoughts on this? And if I swim in a pool that has this, will I get sick?