1. The shrimp idea mulron suggested is very good, it saves you alot of hasle in replacing fish because they are always dieing. and it is also a little inhuman. the shrimp is just a raw uncooked cocktail shrimp from the store.
2. as for that sand idea, also another very good suggestion. if you can i would try to get ahold of Southdown playsand if it is available at your local Home depot. this is good because it has a good mix of grain size. when adding the sand you can either just dump it in or rinse it of. you will get arguments both ways but just do what makes you feel comforitable. Also the reason you want a 3-5 inch sand bed is because this allows nitrates to be broken down in the bottom layers of the sand which pretty much the same as using a filter.
3. Live rock, Get as much as you can afford. 1-2 lbs per gallon is what the ideal amount of rock is. this also acts as a very good biofilter because all the little creatures on the rock will feed on the excess nutrients in the water. if you cannot afford all this rock at once that is ok because when you start the tank your not going to want to load the tank full. GO SLOW. let the tanks Deep Sand Bed (DSB
) and live rock adjust to your bioload.
4. Skimmers in my opinion are great. i'm a newbie in the saltwater business so ive personally never gone skimmerless but i believe that by adding a skimmer it allows you a little bit of a cushion for error. the skimmer will basically pull excess nutrients and dirty crap out of your water keeping it cleaner longer.
i myself have a 65 so if you look at my profile it will tell you my set up and if you have any questions PM me. i'll try to answer them the best i can and if i can't i know most of these people here can. Welcome to Aquarium advice. hope you like it. and sorry for such a long post.