diff --git a/environment.yml b/environment.yml
index ded37a6..8a78adb 100644
--- a/environment.yml
+++ b/environment.yml
@@ -10,6 +10,7 @@ dependencies:
   - ipywidgets>=0.6.0
   - mkl
   - pip:
-    - pymatsolver
-    - discretize
-    - SimPEG
+    - geoana==0.0.5
+    - pymatsolver==0.1.2
+    - discretize==0.3.8
+    - SimPEG==0.10.4
diff --git a/requirements.txt b/requirements.txt
index 8461352..21b0441 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,6 +2,7 @@ numpy
 scipy
 matplotlib
 ipywidgets
-discretize
-SimPEG
-pymatsolver
+geoana==0.0.5
+pymatsolver==0.1.2
+discretize==0.3.8
+SimPEG==0.10.4