diff --git a/megaradrp/recipes/calibration/arc.py b/megaradrp/recipes/calibration/arc.py
index ae873710..43a2e30e 100644
--- a/megaradrp/recipes/calibration/arc.py
+++ b/megaradrp/recipes/calibration/arc.py
@@ -370,7 +370,7 @@ def calibrate_wl(self, rss, lines_catalog, poldeg, tracemap, nlines,
 
                     # store results for plotting
                     plot_tracenumber.append(fibid)
-                    plot_npeaksfound.append(nlines)
+                    plot_npeaksfound.append(len(fxpeaks))
                     plot_crval1.append(solution_wv.cr_linear.crval)
                     plot_cdelt1.append(solution_wv.cr_linear.cdelt)
                     plot_coeff.append(solution_wv.coeff)