The biggest problem with those aquarium coolers like the one mentioned above, is volume. They are designed to cool a lot higher volume of liquid constantly. Having a very small volume in just the pipes + rad can cause issues, especially with condensation buildup. Those compressors are built to run 24/7, it's actually detrimental to have the constant off/on that a small volume cooler will create as the liquid gets chilled/heated. The best way to incorporate a chiller like those is to actually use a fish tank as the reservoir, lowering extreme temperature variations of the actual liquid. Cpu temp has very little to do with the liquid temp, and it's the liquid temp that's going to be controlling the thermostat in the chiller. This isn't a new idea it's been floating around for years, and has never really gotten a following due to the needs of the chiller to be successful. Not many ppl want a fish tank sitting next to the pc.
My suggestion would be to look into peltier cooling, or a full custom loop and bite the bullet about liquid maintenance. Everybody loves the idea of a Lamborghini, nobody loves the price tag to maintain it. You want uber cooling for an uber cpu, it's gonna take some user input monthly.