We employ backscatter in the FESOM2 multiresolution ocean model with a quasi-uniform 1/4°. In multidecadal ocean simulations, backscatter increases eddy activity by a factor 2 or more, moving the simulation closer to observational estimates of sea surface height variability. Moreover, mean sea surface height, temperature, and salinity biases are reduced. This amounts to a globally averaged bias reduction of around 10% for each field, which is even larger in the Antarctic Circumpolar Current. However, in some regions such as the coastal Kuroshio backscatter leads to a slight over-energizing of the flow, and in the Antarctic to an unrealistic reduction of sea ice. Some of the bias increases can be reduced by a retuning of the model and we suggest related adjustments to the backscatter scheme. The backscatter simulation is about 2.5 times as expensive as a simulation without backscatter. Most of the increased cost is due to a halving of the time step to accommodate higher simulated velocities.