diff --git a/Project.toml b/Project.toml
index b003aecd..fb57c37a 100644
--- a/Project.toml
+++ b/Project.toml
@@ -14,6 +14,7 @@ MLJLinearModels = "6ee0df7b-362f-4a72-a706-9e79364fb692"
 NNlib = "872c559c-99b0-510c-b3b7-b6c96a88d5cd"
 Optim = "429524aa-4258-5aef-a3af-852621145aeb"
 PartialFunctions = "570af359-4316-4cb7-8c74-252c00c2016b"
+Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 
@@ -29,6 +30,7 @@ LinearAlgebra = "1.10"
 MLJLinearModels = "0.9.2"
 NNlib = "0.8.4, 0.9"
 Optim = "1"
+PartialFunctions = "1.2"
 Random = "1"
 SafeTestsets = "0.1"
 SparseArrays = "1.10"
diff --git a/src/ReservoirComputing.jl b/src/ReservoirComputing.jl
index 84b0d145..c826b3f3 100644
--- a/src/ReservoirComputing.jl
+++ b/src/ReservoirComputing.jl
@@ -9,6 +9,8 @@ using LinearAlgebra
 using MLJLinearModels
 using NNlib
 using Optim
+using PartialFunctions
+using Random
 using SparseArrays
 using Statistics
 
diff --git a/src/esn/esn_reservoirs.jl b/src/esn/esn_reservoirs.jl
index 047fb0bf..fa57109b 100644
--- a/src/esn/esn_reservoirs.jl
+++ b/src/esn/esn_reservoirs.jl
@@ -23,11 +23,11 @@ This type of reservoir initialization is commonly used in ESNs for capturing tem
 function rand_sparse(rng::AbstractRNG,
         ::Type{T},
         dims::Integer...;
-        radius = 1.0,
-        sparsity = 0.1) where {T <: Number}
+        radius = T(1.0),
+        sparsity = T(0.1)) where {T <: Number}
     reservoir_matrix = Matrix{T}(sprand(rng, dims..., sparsity))
-    reservoir_matrix = 2.0 .* (reservoir_matrix .- 0.5)
-    replace!(reservoir_matrix, -1.0 => 0.0)
+    reservoir_matrix = T(2.0) .* (reservoir_matrix .- T(0.5))
+    replace!(reservoir_matrix, T(-1.0) => T(0.0))
     rho_w = maximum(abs.(eigvals(reservoir_matrix)))
     reservoir_matrix .*= radius / rho_w
     if Inf in unique(reservoir_matrix) || -Inf in unique(reservoir_matrix)
@@ -62,7 +62,7 @@ Rodan, Ali, and Peter Tino. "Minimum complexity echo state network." IEEE Transa
 function delay_line(rng::AbstractRNG,
         ::Type{T},
         dims::Integer...;
-        weight = 0.1) where {T <: Number}
+        weight = T(0.1)) where {T <: Number}
     reservoir_matrix = zeros(T, dims...)
     @assert length(dims) == 2 && dims[1] == dims[2],
     "The dimensions must define a square matrix (e.g., (100, 100))"
diff --git a/test/esn/test_reservoirs.jl b/test/esn/test_reservoirs.jl
index ac751712..df58bd3c 100644
--- a/test/esn/test_reservoirs.jl
+++ b/test/esn/test_reservoirs.jl
@@ -1,79 +1,36 @@
 using ReservoirComputing
+using LinearAlgebra
+using Random
+include("../utils.jl")
 
 const res_size = 20
 const radius = 1.0
 const sparsity = 0.1
 const weight = 0.2
 const jump_size = 3
+const rng = Random.default_rng()
+
+dtypes = [Float16, Float32, Float64]
+reservoir_inits = [rand_sparse]
+
+@testset "Sizes and types" begin
+    for init in reservoir_inits
+        for dt in dtypes
+            #sizes
+            @test size(init(res_size, res_size)) == (res_size, res_size)
+            @test size(init(rng, res_size, res_size)) == (res_size, res_size)
+            #types
+            @test eltype(init(dt, res_size, res_size)) == dt
+            @test eltype(init(rng, dt, res_size, res_size)) == dt
+            #closure
+            cl = init(rng)
+            @test cl(dt, res_size, res_size) isa AbstractArray{dt}
+        end
+    end
+end
+
+@testset "rand_sparse" begin
+    sp = rand_sparse(res_size, res_size)
+    @test check_radius(sp, radius)
+end
 
-#testing RandSparseReservoir implicit and esplicit constructors
-reservoir_constructor = RandSparseReservoir(res_size, radius, sparsity)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-
-reservoir_constructor = RandSparseReservoir(res_size, radius = radius, sparsity = sparsity)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-
-#testing PseudoSVDReservoir implicit and esplicit constructors
-reservoir_constructor = PseudoSVDReservoir(res_size, radius, sparsity)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) <= radius
-
-reservoir_constructor = PseudoSVDReservoir(res_size, max_value = radius,
-    sparsity = sparsity)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) <= radius
-
-#testing DelayLineReservoir implicit and esplicit constructors
-reservoir_constructor = DelayLineReservoir(res_size, weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-reservoir_constructor = DelayLineReservoir(res_size, weight = weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-#testing DelayLineReservoir implicit and esplicit constructors
-reservoir_constructor = DelayLineBackwardReservoir(res_size, weight, weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-reservoir_constructor = DelayLineBackwardReservoir(res_size, weight = weight,
-    fb_weight = weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-#testing SimpleCycleReservoir implicit and esplicit constructors
-reservoir_constructor = SimpleCycleReservoir(res_size, weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-reservoir_constructor = SimpleCycleReservoir(res_size, weight = weight)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-#testing CycleJumpsReservoir implicit and esplicit constructors
-reservoir_constructor = CycleJumpsReservoir(res_size, weight, weight, jump_size)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-reservoir_constructor = CycleJumpsReservoir(res_size, cycle_weight = weight,
-    jump_weight = weight, jump_size = jump_size)
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
-@test maximum(reservoir_matrix) == weight
-
-#testing NullReservoir constructors
-reservoir_constructor = NullReservoir()
-reservoir_matrix = create_reservoir(reservoir_constructor, res_size)
-@test size(reservoir_matrix) == (res_size, res_size)
diff --git a/test/utils.jl b/test/utils.jl
new file mode 100644
index 00000000..9ef6f360
--- /dev/null
+++ b/test/utils.jl
@@ -0,0 +1,5 @@
+function check_radius(matrix, target_radius; tolerance=1e-5)
+    eigenvalues = eigvals(matrix)
+    spectral_radius = maximum(abs.(eigenvalues))
+    return isapprox(spectral_radius, target_radius, atol=tolerance)
+end
\ No newline at end of file