What else is in the tank?
If not, what have you added to start the cycle?
Read this article
about fishless cycling.
My 125 was cloudy for a week before it started to settle. I had some LR
to start the cycle. I was assured by the advisors here that the bacteria would grow and attach to the particles and it would eventyually settle down. I can now pick up a handfull and it will settle within minutes of being dropped back down.