Greetings... I am contemplating a liquid chiller using TEC and water blocks in a sandwich formation:

{heatsink}
{60 watt TEC}
{warm-side water block to warm-water reservoir}
{90 watt TEC}
{cold-side water block to cold-water reservoir}
{90 watt TEC}
{warm-side water block to warm-water reservoir}
{60 watt TEC}
{heatsink}

All liquids run at 3L/min
The warm-sides run parallel (effectively 1.5L/min)
The purpose of the outside TECs is to provide secondary cooling when ambient is too high.
Ultimately, I'd like to remove 520 watts over two hours with a 32 degree C delta.

Thoughts, comments, concerns?