diff --git a/src/imgdata.rs b/src/imgdata.rs
index bc9d2b2..7abf72e 100644
--- a/src/imgdata.rs
+++ b/src/imgdata.rs
@@ -21,8 +21,7 @@ impl ThinGridData {
         }
     }
 
-    #[allow(dead_code)]
-    pub fn new_from_grid_vec(in_grids: Vec<Grid>) -> Vec<Self> {
+    pub fn new_from_grid_vec(in_grids: &[Grid]) -> Vec<Self> {
         in_grids
             .iter()
             .map(|grid| Self::new_from_grid(grid))
diff --git a/src/model.rs b/src/model.rs
index 2668756..d09a800 100644
--- a/src/model.rs
+++ b/src/model.rs
@@ -148,7 +148,7 @@ impl Model {
     }
 
     fn save_image_data(&mut self) {
-        let grids = ThinGridData::new_from_grid_vec(self.population_grids.clone());
+        let grids = ThinGridData::new_from_grid_vec(&self.population_grids);
         let img_data = ImgData::new(grids, self.palette);
         self.img_data_vec.push((self.iteration + 1, img_data));
         let size: usize = std::mem::size_of_val(&self.img_data_vec);