Join Date: Jan 2013
Location: NE Victoria, Ausrtalia
If you want a tank similar to the one's above there are a few things you should look at. First notice how the substrate in nearly all the tanks you look at is higher at the back than at the front? This is to create the illusion of greater depth. This is one thing your tank needs.
Secondly it is best if you have a lot of options when you are choosing which rocks to use. That means if you intend on using say 3 rocks in your tank than have maybe 10 to choose from. I agree with thelub about where to get rocks. But depending on where you live you might be easily able to find rocks for free that you like. Have a look around, go out of town, have a look on the side of roads etc. I have never bought a rock for a tank in my life.
When you have your rocks it would be a good idea to get a cardboard box as close to the size of your tank as possible, you can even make one considering your tank is so small. The reason for this is you can cut the top and most of the front out of the box, just leave say an inch or a bit more of a lip on the lower front edge. So you have a replica of your tank in which you can fiddle with your placement without having to work in underwater etc. Just put some other gravel or potting mix or something in as substrate .
That way you can take a photo of what you like and ask for suggestions/help and it is easy to change it. Once you are happy then you transfer that hardscape to your tank in one move.