public static void registerFluid(FluidStack fluidStack, String reactantName) {
if(!_reactants.containsKey(reactantName)) {
throw new IllegalArgumentException("Unknown reactantName " + reactantName);
}
FluidToReactantMapping mapping = new FluidToReactantMapping(fluidStack, reactantName);
SourceProductMapping reverseMapping = mapping.getReverse();
_fluidToReactant.put(mapping.getSource(), mapping);
mapReactant(reverseMapping.getSource(), reverseMapping, _reactantToFluid);
}