Its a relief Gokul and Karan have cracked the (rather non-existent) problem with the tank and water creation..So, great work guys..
Here's the material specifications for water:
Fresnel: 0 <---- Very important if you want a coloured liquid.
Enable TraShad as well.
For the colours I used a dark one for the Col value
A lighter one for the Spe value
And true white for the Mir one.
Set the Alpha value at 0.355