how to make realistic water for a modern warships?
SMH Responds I assume you are planning some type of diorama involving ships. This is a project I undertook years ago.
First, review the information of ocean-based dioramas at: http://www.scale-modelers-handbook.com/ocean-diorama.html .
To create your "water", I highly recommend a product called Magic Water. You will find instructions and tips in the box which make the process relatively easy. Try to keep your "water" depth as thin as possible.