I have done a couple of experiments to try and run a small chill tank with a 60w peltier cooled with a fan and heatsink, it does work but the temp results are not fantastic.I found its better to run another waterblock cooled with a heatsink/fan in the system loop just before cpu entry.It does make a difference.
I have just made an aluminium heatsink to be cooled with an 80mm fan against 2 peltiers with a waterblock covering about a 90mm span in the loop prior to cpu.
It's just about done and I'll post some pics when done, I figure it should work ok....so I'll keep you posted.
stevo