diff --git a/inputs/exacb_turbulence.in b/inputs/exacb_turbulence.in
index c3e8f18a..a441161b 100644
--- a/inputs/exacb_turbulence.in
+++ b/inputs/exacb_turbulence.in
@@ -57,7 +57,7 @@ corr_time    = 1.0      # autocorrelation time of the OU forcing process
 rseed        = 20190729 # random seed of the OU forcing process
 sol_weight   = 1.0      # solenoidal weight of the acceleration field
 accel_rms    = 0.5      # root mean square value of the acceleration field
-num_modes    = 30       # number of wavemodes
+num_modes    = 20       # number of wavemodes
 
 <modes>
 k_1_0	= +2