paint the base blue and then fill it with hair gel or clear glue
by Dan Dsp from runescape com. the sky i believe.
No
People have used clear glue, clear silicone etc. but it depends on size and how turbulant. Modelers also use sculpy and sculpt in the waves etc(if you are skilled) then paint. If its a calm lake or...
Food coloring, and other dyes.