diff --git a/src/utils/constants.jl b/src/utils/constants.jl
index 4220124..8403768 100644
--- a/src/utils/constants.jl
+++ b/src/utils/constants.jl
@@ -2,25 +2,6 @@
 
 abstract type PDEParams end
 
-struct FHNParams <: PDEParams
-    N::Int
-    dx::Float64 # grid spacing
-    Du::Float64
-    Dv::Float64
-    ϵ::Float64
-    a::Float64
-    b::Float64
-end
-
-struct GSParams <: PDEParams
-    N::Int       # grid size
-    dx::Float64  # grid spacing
-    Du::Float64  # diffusion rate U
-    Dv::Float64  # diffusion rate V
-    F::Float64   # feed rate
-    k::Float64   # kill rate
-
-end
 
 struct CombinedPDEParams <: PDEParams
     N::Int