Hi, I have a reactor setup existing out of 4 reactors. The reactors use uranium-235 fuel cells, but the output from the reactor is not what I would expect. It reports at a temperature between 975 - 980 (at 980 ECCS kicks in cooling it to around 975) to have an efficiency of 196% and a power output of 126 MW. Looking over the spreadsheets I've only found similar values with MOX fuel if the efficiency comes from 4 reactors (198) and the power from 3 (126).

I am using a lot of other mods, the fuel comes from the base mod but is edited by MadClown01's Vanille Nuclear > Angel's Industries > Artisanal Reskins: Angel's Mods > Bob's Metals, Chemicals and Intermediates mod > Angel's Industries.

Speaking of Angel's and Bob's does this mod support them? And another thing on the topic of Angel's, placing 2 Arthurium fast burner reactors next to each other causes a crash:
The mod Realistic Reactors (3.1.4) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event RealisticReactors::on_built_entity (ID 6)
RealisticReactors/scripts/heat/network.lua:498: attempt to index local 'q' (a nil value)
stack traceback:
RealisticReactors/scripts/heat/network.lua:498: in function 'add_entity_to_network_cell'
RealisticReactors/scripts/heat/network.lua:555: in function 'add_reactor'
RealisticReactors/scripts/events/construct.lua:101: in function 'entity'
RealisticReactors/control.lua:51: in function <RealisticReactors/control.lua:50>

The function causing the crash is the one, which checks if reactors are connected by heat pipe. You can't build reactors nect to each other, doesn't matter if the are modded ones or the vanilla one.
Regarding the output and compatibility questions...: sorry, I dont remember, it's been too long... :)
But if I remember correct most modded fuels should be technically compatible, they just might produce unrealistic high or low output.