diff --git a/core/dive.cpp b/core/dive.cpp
index 89d2d60e0..544900989 100644
--- a/core/dive.cpp
+++ b/core/dive.cpp
@@ -1042,6 +1042,27 @@ static void fixup_dc_sample_sensors(struct dive &dive, struct divecomputer &dc)
 	}
 }
 
+static void fixup_dc_cylinder_use(struct dive &dive, struct divecomputer &dc)
+{
+
+	if (dc.divemode != OC && dc.divemode != CCR && dc.divemode != PSCR)
+		return;
+
+	// Check that we have at least one cylinder that is suitable for the dive
+
+	// For OC we default to air if we don't have any cylinders
+
+	if (dc.divemode == OC && dive.cylinders.empty())
+		return;
+
+	for (auto &cylinder: dive.cylinders)
+		if ((dc.divemode == CCR && cylinder.cylinder_use == DILUENT) || ((dc.divemode == PSCR || dc.divemode == OC) && cylinder.cylinder_use == OC_GAS))
+			return;
+
+	report_error("Dive: %u, dive computer: %s: %s dive, but no %s cylinder found. Please add or select the correct cylinder use.", dive.number, dc.model.c_str(), dc.divemode == OC ? "open circuit" : dc.divemode == CCR ? "CCR" : "PSCR", dc.divemode == OC ? "open circuit" : dc.divemode == CCR ? "diluent" : "drive gas");
+}
+
+
 static void fixup_dive_dc(struct dive &dive, struct divecomputer &dc)
 {
 	/* Fixup duration and mean depth */
@@ -1070,6 +1091,9 @@ static void fixup_dive_dc(struct dive &dive, struct divecomputer &dc)
 	/* Fixup CCR / PSCR dives with o2sensor values, but without no_o2sensors */
 	fixup_no_o2sensors(dc);
 
+	/* Fixup cylinder use */
+	fixup_dc_cylinder_use(dive, dc);
+
 	/* If there are no samples, generate a fake profile based on depth and time */
 	if (dc.samples.empty())
 		fake_dc(&dc);
diff --git a/core/gas.cpp b/core/gas.cpp
index 0ef4033ba..ca1e076fe 100644
--- a/core/gas.cpp
+++ b/core/gas.cpp
@@ -62,8 +62,9 @@ void sanitize_gasmix(struct gasmix &mix)
 	/* Sane mix? */
 	if (o2 <= 1000 && he <= 1000 && o2 + he <= 1000)
 		return;
-	report_info("Odd gasmix: %u O2 %u He", o2, he);
+
 	mix = gasmix_air;
+	report_error("Odd gasmix: %u O2 %u He, switched to air.", o2, he);
 }
 
 int gasmix_distance(struct gasmix a, struct gasmix b)