diff --git a/ArduSub/config.h b/ArduSub/config.h
index c90a6a7c47..8b7f1608bf 100644
--- a/ArduSub/config.h
+++ b/ArduSub/config.h
@@ -77,7 +77,7 @@
 #endif
 
 #ifndef SURFACE_DEPTH_DEFAULT
- # define SURFACE_DEPTH_DEFAULT -0.10 // pressure sensor reading 10cm depth means craft is considered surfaced
+ # define SURFACE_DEPTH_DEFAULT -10.0 // pressure sensor reading 10cm depth means craft is considered surfaced
 #endif
 
 
diff --git a/ArduSub/control_althold.cpp b/ArduSub/control_althold.cpp
index dc382877e1..42945b8ca0 100644
--- a/ArduSub/control_althold.cpp
+++ b/ArduSub/control_althold.cpp
@@ -129,7 +129,7 @@ void Sub::althold_run()
             	pos_control.set_alt_target_from_climb_rate_ff(target_climb_rate, G_Dt, false);
         	} else if(pos_control.get_vel_target_z() > 0.0) {
         		pos_control.relax_alt_hold_controllers(0.0); // clear velocity and position targets, and integrator
-        		pos_control.set_alt_target(g.surface_depth*100); // set alt target to the same depth that triggers the surface detector.
+        		pos_control.set_alt_target(g.surface_depth); // set alt target to the same depth that triggers the surface detector.
         	}
         } else {
         	pos_control.set_alt_target_from_climb_rate_ff(target_climb_rate, G_Dt, false);
diff --git a/ArduSub/surface_bottom_detector.cpp b/ArduSub/surface_bottom_detector.cpp
index 2f91c2ad63..23b88022b5 100644
--- a/ArduSub/surface_bottom_detector.cpp
+++ b/ArduSub/surface_bottom_detector.cpp
@@ -21,7 +21,7 @@ void Sub::update_surface_and_bottom_detector()
 	if (ap.depth_sensor_present) { // we can use the external pressure sensor for a very accurate and current measure of our z axis position
 		current_depth = barometer.get_altitude();
 
-		set_surfaced(current_depth > g.surface_depth); // If we are above surface depth, we are surfaced
+		set_surfaced(current_depth > g.surface_depth/100.0); // If we are above surface depth, we are surfaced
 
 		if(motors.limit.throttle_lower && vel_stationary) {
 			// bottom criteria met - increment the counter and check if we've triggered