Ahhhhh, you're gonna make a lot of progress today. Wash, wash, wash the sand. And then wash it some more. It's not the end of the world if the water clouds, but if you can prevent it by washing it a couple more times, then why not?
The 3 filter pads should be in the same basket, so you will need to get some media for the other baskets. When stacking media, its best to go coarsest to finest. You don't want to have fine media at the bottom or else it will clogged quickly. I use fluval ceramic prefilters in the bottom tray, but you could also get some coarse foam and use some of that to trap the large particles. In the top tray I use biomax. Matrix is another good biomedia to use. There are a lot of ways to set up the media - as long as it goes from coarsest to finest.
I would leave the UV off. In adddition to saving bulb life, it will save money too. The water moves through the filter too fast for the UV to be effective as a preventative measure. It may clear green water though, if you ever get it. Green water is an algae bloom in the water.
lucky lucky!
