This sounds very much like a bacterial bloom. A common occurence with newly set up aquariums.
This cloudiness will naturally disipate over a few days or a week or so, depends on how fast the tank settles. Don't worry, its harmless and your tank and plants will be perfectly fine.
Basically its just the bacterias all over the internals of the tank and also in the filter growing and establishing.
I'd strongly recommend you to have a read of this article, it is most useful and a good guide on ensuring your tank and filter is ready before you add any livestock to the tank otherwise the livestock may suffer illnesses and possibly die within a short space of time.
Cycling Your New Fresh Water Tank: Read This First!
Oh and welcome to the forum btw