fresh saltwater mix wierd problems ?

so i left around 50 litres of saltwater to mix overnight in a tub being circulated by a return pump, now in the morning its still cloudy ?, also i turned the powerhead off 5 or 6 hrs ago and its still cloudy .. but the main thing thats making me unsure about using it is im using my refractometer and i am not getting any reading at all the chart is all white .. what the ? .. has anyone had this happen before ?:help::confused: im planning on checking my MG/CA/ALK and if they all checkout ok ill add it but if not i may have to turf it ? .. sucks cause i used up pretty much the last 1/3 of my salt bucket making this mix for a large water change today after the cycle finished and ive only got enough salt left for a small change next weekend till i get paid again and can pickup another bucket, any ideas guys ? got me stumped as to why im not getting a reading at all .. cant find anything on google about it at all seems nobody has had this problem ? ..