There are numerous ancient civilizations that have awesome fish tank decorations these days. These include the Mayans, Asian and the always famous Greek ruins. Using any of these would create stunning scenes of times gone by, producing an air of wonder and discovery in your very own room.
The one ancient civilization that I personally love to use in my tank designs is the Ancient Egyptians. Who has not seen at least a photograph of the Great Pyramids or the towering mighty Sphinx. With the cool and extremely detailed tank ornaments you can get these days, you will be able to bring the exact replica of the Egyptian landscape into your aquarium.
With the Egyptian tank decor, you basically have a couple of options. You could create an outdoor scene, an indoor scene or just use Egyptian artifacts.
To create an outdoor Egyptian scene, you would be utilizing replicas of the massive structures that are synonym to Egypt. These would include the pyramids as well as the Sphinx. This is placed on top of a sand colored gravel to give it the impression of being in the desert. If you plan to use plants, they should not be of the leafy variety. Java Moss is one option you can look into. To make the theme work, a great idea is to place a fish tank background depicting a desert scene. This would give it a 3D effect to the whole design.
For the indoor effect, you would use indoor structures such as Egyptian columns as well as the Pharaoh's sarcophagus. Place them to look like a scene from an archaeological dig. The gravel would still be sand colored. As a backdrop, you could either use one depicting Egyptian hieroglyphs or a rock face. These days you would be able to get 3D rock backgrounds where the rocks protrude out instead of a flat print. This makes theme look so much more realistic. Being indoors, you would not place any plants because they might make the theme look odd. You may place rocks if you wish, just make them out to look like they came crashing down from the roof of a temple. This means simply scattering them around the decor. Try not getting smooth faced river rocks, the ones you get should look as if they were once bricks that made up the walls.
Egyptian artifacts are new additions to the fish tank decorating scene. The most common ones that you can find are the Egyptian vases. Though they are only aquarium decor, they are made to look extremely authentic. What I love about the Egyptian vases is the holes that they always have in the side. These make awesome caves for the fish and if you have been following my posts all these years, you would know that I am big on caves for aquariums. Apart from the vases, another really cool tank ornament that I love a whole lot is a bust of Pharaoh. The bust is golden in color and looks very regal. With these ornaments, placing normal aquatic plants around them as well as using other types of gravel are not an issue.
The key point here is that your design needs to look old. It needs to look like an archaeological photo that you might see in the National Geographic magazine. Scan the internet for images that will help you get an idea of what to go for.