This reactor setup has 6500 cold fluoroketone in the tank and generates 400 MW inside the inner system. However, once I get out to the edge and beyond I start to have severe power fluctuations and power generation drops below 100 MW and eventually into the negative and then sputters terribly. I don't see any way to troubleshoot the issue and can't understand why the generators suddenly generate less power.
Remember that the generators themselves CONSUME power. Not as much as the turbines produce of course, but that means that fusion is crap at starting itself from a black or severe brownout.
Try adding some accumulators+solar to kickstarter when it's dead.
The Fluid port for the Top reactor appears to be connected directly to the Output of your Cryoplant; NOT to a pipe or Tank. So the excess Fluid on the tank can never make it into the reactors, since the Cryoplant’s ports are one-way (output). You can see this in the small “triangles” at the ports.
Once the Top reactor becomes Fluid-starved, the bottom one will lose its Neighbor bonuses - hence the drop in output from 400MW to 100MW. Then the Cryoplants will get Low Power and be unable to keep up with demand for fresh Fluid; then it all falls over.