How much water should we be giving 2 year old? Currently my 2 year old drinks about 150ml of plain water, 120ml of gripe water and other fluids such as soup and milk daily.

I have no idea on what's the "suggested" guidelines, but I just let him drink whenever he wants - and also to drink after play! As long as your child is drinking well and pee is colourless with regular wet diapers/trips to toilet, then not to worry :)