Hello
and welcome no1bubba
First off how "New" is this tank?
Try to get a picture (Camera phones do a decent job) so we can be more accurate in our suggestions.
Where is your "Source" water coming from? Is it RO/DI?
What type of lighting are you running?
What type of filtration ?
What are your current tank test results?
How long since your last tank addition (last new fish etc).
Many times a "New Tank" has what's been suggested above as "Diatom Bloom". If that IS the case here don't sweat it. It's just part of many new tanks. Your clean up crew will take care of it. What do you have FOR a clean up crew? Sounds like your tank may already be on the "HEAVY" side if it's new. If it IS new let's take a big deep breath and slow down. We have a LOT to learn in order to get this right. That's the FUN of it.
Again welcome to the Reef