ntvflgirl is right- read, read and read again.
IMO, (in my opion) I would use the souhtdown sand if you can find it, and do not rinse it. That small stuff is what you want in the tank. It'll take a week to clear, but you'll like it in the end. If you can't get that, go with another type of sand like quickcrete play sand. CC is the same as the pebble stuff you have, meaning it will clog up and that will mean more maintiance.
Live rock is good to also, it helps with the break down of waste and hiding places for fish and other organisms. You can make your own if money is a problem and time is on your hands. here is a web site that will tell you how.
garf.org
I have done alot of DIY projects and saved alot of money. But I like to do that kind of stuff also.
The biggest mistake IMO people make in this hobby is they want an instint reef or FO (fish only) tank. It take's time, you must take your time or you will have problems later on down the road.
Please read some of the posts and search for a good book or website, and read.
HTH (hope this helps) good luck and welcome to the board.
DBurr
PS if you can't return the pebbles, use them in potted plants, it looks great.
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