I bought a used Aquaone nano 60 and set it up to cycle before I went away for a week. I came back to a tank which is still not clear and a covering of 'dust' over the plants. I also have had to top up the water but am having issues with the filter pump compartment being low of water. I cannot add any more or it will overflow from the main tank area. I had set the tank filtration up as per the instruction and have rinsed the sponge since getting back. However the level is still low. Any ideas/help appreciated.