The Golden Ratio
Working with the rule of thirds, or "หThe Golden Ratio'
The Golden Ratio was realised by the ancient Greeks and has been used in all art forms for thousands of years. It provides a guide to achieve the perfect balance within a work of art, or any endeavour that involves placing objects in a space.
How to use it
Imagine that there are four lines (two horizontal and two vertical) running through your tank, splitting it into nine equal sections. Wherever the lines cross is a golden focus point for your aquascape, and marks where you should consider positioning prominent features like main stones, wood shapes or bold/red plant species. The same process can be done when considering planning the height of plants and hard-scape; place the focal points at 1/3 or 2/3 of the height of the tank, and remember to consider the height that your plants will grow to. You can use it to plan the overall scape of your tank, for example you can choose to have 1/3 planted and 2/3 negative space, or vice versa. There are almost an infinite number of combinations to play with, and all can help you achieve stunning results.
Good luck!