Looking at this more closely, it would seem that the primary test they were doing with this was the effectiveness of the external heat exchangers. They had one

Looking at this more closely, it would seem that the primary test they were doing with this was the effectiveness of the external heat exchangers. They had one rack consuming 27kW maximum, but they had 5 large external heat exchangers (of two different designs) and all kinds of external tubing and valves to manage the cooling fluid flow. Seems like overkill unless they were running tests on the effect of different operating temperatures on biofouling and vice versa.