My idea was to connect tubes to the reactor which would carry the heat to some type of cooling block, and carry the cooled fluid back into the reactor and does the same cycle again. The more cooling blocks you connect to the tubes, the more colder the fluid will be, which will absorb more heat, and do it faster. The coldest color may can be black, and the hottest is green , because some of the radiation leaked into it which made it really hot. Also there could be different classes of cooling blocks to maintain heat for a specific reactor like a Mark 5 or maybe just a Mark 2. It could maybe work the other way, with breeders, adding heat with a heater the fluid will maintain heat in the reactor, so you don't have to build a heat balancing system inside.
Recipes:
Tube for the fluid:
The cooling thing(i dont know what name i should give it, you give it a name :D):
C= the integrated cooling thing for the reactor
C C
C C
It would have a gui for how much coolant is stored in it, and how much energy it is receiving(the more energy it has the more colder the coolant will be)
And the heater:
(just supply a steady amount of power maybe like 20 eu/t, will also have a setting on how hot you want the coolant to be)
all you have to do is attach the tubes to the reactor, then attach it to the cooling things or the heaters, then wire it to some gens. you can also atatch more then ne tube to the reactor.