This is why i don't use water cooling.
Anyway, salvage the harddrive, cd drive and maybe RAM.
Your graphics is maybe only damaged on the fan.
Watercooling gets a bad name for events like these. If you ever do water-cool again, go custom with a NON CONDUCTIVE FLUID. Not deionized water, that becomes conductive after it touches metal. Conductive fluid is super stone age. Check with Corsair about any sort of guarantee not to leak.