Red Slime.. guh

[marknash]

So.. we have a 46g tank with 2 koralia 3's.. and a protein skimmer.. (not sure the flow rating) we feed our 6 fish a cube of mysis (maybe a bit less soaked in garlic and some multivits) and a bit of flake per day. we've reduced our lighting time.. increased our water changes.. switched to RO water.. increased our flow in the tank and we are still getting this stuff!? im kind of at a loss of why this cyano sp? is in our tank.
I was reading about uv sterilizers.. we dont have one of those.. what are those thigns for...would that help?
i have narrowed it down to...could it have anything to do with the fact we only have about 38lbs of live rock in there, also our clean up crew is small.. and we got our light fixture used.. they guy told us the bulbs were new.. but they could be old i suppose.. could that contribute to our red mess?
Forgive me for the silly questions..we are super new to the hobby.. and am kind of wondering why the heck we are still experiencing this problem!!