diff --git a/src/server/models/Reading.js b/src/server/models/Reading.js
index e257b74a4..ff1991af8 100644
--- a/src/server/models/Reading.js
+++ b/src/server/models/Reading.js
@@ -171,11 +171,6 @@ class Reading {
 		// Separate the result rows by meter_id and return a nested object.
 		const compressedReadingsByGroupID = mapToObject(groupIDs, () => []); // Returns { 1: [], 2: [], ... }
 		for (const row of allCompressedReadings) {
-			// HACK. Something in the SQL is causing these to be weird for some rows.
-			// This solves the problem but is not elegant.
-			if (compressedReadingsByGroupID[row.group_id] === undefined) {
-				compressedReadingsByGroupID[row.group_id] = [];
-			}
 			compressedReadingsByGroupID[row.group_id].push(
 				{ reading_rate: row.reading_rate, start_timestamp: row.start_timestamp, end_timestamp: row.end_timestamp }
 			);
diff --git a/src/server/sql/group/create_groups_tables.sql b/src/server/sql/group/create_groups_tables.sql
index 3f076bb8b..cdd3dead6 100644
--- a/src/server/sql/group/create_groups_tables.sql
+++ b/src/server/sql/group/create_groups_tables.sql
@@ -108,11 +108,16 @@ CREATE VIEW groups_deep_meters AS
   */
 
 	WITH all_deep_meters(group_id, meter_id) AS (
-			SELECT DISTINCT -- Distinct because two children might include the same meter, and we only want it once.
-				COALESCE(gdc.parent_id, gim.group_id) AS group_id,
-				gim.meter_id
-			FROM groups_deep_children gdc
-				RIGHT JOIN groups_immediate_meters gim ON gdc.parent_id = gim.group_id OR gdc.child_id = gim.group_id
+		SELECT DISTINCT -- Distinct because two children might include the same meter, and we only want it once.
+			gdc.parent_id AS group_id,
+			gim.meter_id AS meter_id
+		FROM groups_immediate_meters gim
+			INNER JOIN groups_deep_children gdc ON gdc.child_id = gim.group_id
+		UNION
+		SELECT
+			gim.group_id AS group_id,
+			gim.meter_id AS meter_id
+		from groups_immediate_meters gim
 	)
 	SELECT
 		adm.group_id AS group_id,
diff --git a/src/server/sql/reading/create_function_get_compressed_groups_readings.sql b/src/server/sql/reading/create_function_get_compressed_groups_readings.sql
index d39d798ff..cd356b5d5 100644
--- a/src/server/sql/reading/create_function_get_compressed_groups_readings.sql
+++ b/src/server/sql/reading/create_function_get_compressed_groups_readings.sql
@@ -13,7 +13,7 @@ CREATE OR REPLACE FUNCTION compressed_group_readings(
 	BEGIN
 		SELECT array_agg(meter_id)
 		INTO meter_ids
-		FROM groups_immediate_meters gdm
+		FROM groups_deep_meters gdm
 		INNER JOIN unnest(group_ids) gids(id) ON gids.id = gdm.group_id;
 
 		RETURN QUERY
@@ -24,6 +24,9 @@ CREATE OR REPLACE FUNCTION compressed_group_readings(
 				compressed.end_timestamp AS end_timestamp
 			FROM compressed_readings(meter_ids, from_timestamp, to_timestamp, num_points) compressed
 			INNER JOIN groups_deep_meters gdm ON gdm.meter_id = compressed.meter_id
+			-- The previous line would include groups that are parents of the groups we want,
+			-- so we remove those groups that are not requested here
+			INNER JOIN unnest(group_ids) gids(group_id) ON gdm.group_id = gids.group_id
 			GROUP by gdm.group_id, compressed.start_timestamp, compressed.end_timestamp
 			ORDER BY gdm.group_id, compressed.start_timestamp;
 	END;
diff --git a/src/server/sql/reading/create_function_get_group_barchart_readings.sql b/src/server/sql/reading/create_function_get_group_barchart_readings.sql
index ba6b09ecd..94f3c17ee 100644
--- a/src/server/sql/reading/create_function_get_group_barchart_readings.sql
+++ b/src/server/sql/reading/create_function_get_group_barchart_readings.sql
@@ -9,7 +9,7 @@ CREATE OR REPLACE FUNCTION barchart_group_readings(
 	BEGIN
 		SELECT array_agg(meter_id)
 		INTO meter_ids
-		FROM groups_immediate_meters gdm
+		FROM groups_deep_meters gdm
 			INNER JOIN unnest(group_ids) gids(id) ON gids.id = gdm.group_id;
 
 		RETURN QUERY
@@ -20,6 +20,9 @@ CREATE OR REPLACE FUNCTION barchart_group_readings(
 			compressed.end_timestamp AS end_timestamp
 		FROM barchart_readings(meter_ids, duration, from_timestamp, to_timestamp) compressed
 			INNER JOIN groups_deep_meters gdm ON gdm.meter_id = compressed.meter_id
+			-- The previous line would include groups that are parents of the groups we want,
+			-- so we remove those groups that are not requested here
+			INNER JOIN unnest(group_ids) gids(group_id) ON gdm.group_id = gids.group_id
 		GROUP by gdm.group_id, compressed.start_timestamp, compressed.end_timestamp;
 	END;
 $$ LANGUAGE plpgsql;
diff --git a/src/server/test/db/compressedReadingsTests.js b/src/server/test/db/compressedReadingsTests.js
index f871380a7..147f220d3 100644
--- a/src/server/test/db/compressedReadingsTests.js
+++ b/src/server/test/db/compressedReadingsTests.js
@@ -11,6 +11,7 @@ const expect = chai.expect;
 
 const recreateDB = require('./common').recreateDB;
 const db = require('../../models/database').db;
+const Group = require('../../models/Group');
 const Meter = require('../../models/Meter');
 const Reading = require('../../models/Reading');
 
@@ -96,4 +97,50 @@ mocha.describe('Compressed Readings', () => {
 
 		expect(result).to.deep.equal({ [meter.id]: [] });
 	});
+
+	mocha.describe('With groups, meters, and readings set up', async () => {
+		let meter2;
+		const startTimestamp = moment('2017-01-01');
+		const endTimestamp = moment('2017-01-01').add(1, 'hour');
+		const readingValue = 10;
+		mocha.beforeEach(async () => {
+			// Groups A and B will each contain a meter
+			const groupA = new Group(undefined, 'A');
+			const groupB = new Group(undefined, 'B');
+			// Group C will contain A and B
+			const groupC = new Group(undefined, 'C');
+			await Promise.all([groupA, groupB, groupC].map(group => group.insert()));
+
+			// Create and get a handle to a new meter
+			await new Meter(undefined, 'Meter2', null, false, Meter.type.MAMAC).insert();
+			meter2 = await Meter.getByName('Meter2');
+
+			// Place meters & groups in hierarchy
+			await groupA.adoptMeter(meter.id);
+			await groupB.adoptMeter(meter2.id);
+			await groupC.adoptGroup(groupA.id);
+			await groupC.adoptGroup(groupB.id);
+
+			// Add some readings to the meters
+			const reading1 = new Reading(meter.id, readingValue, startTimestamp, endTimestamp);
+			const reading2 = new Reading(meter2.id, readingValue, startTimestamp, endTimestamp);
+			await Reading.insertAll([reading1, reading2]);
+		});
+		mocha.it('can get readings from a group containing meters', async () => {
+			const groupA = await Group.getByName('A');
+			const actualReadings = await Reading.getCompressedGroupReadings([groupA.id], null, null, 1);
+			expect(actualReadings[groupA.id]).to.have.lengthOf(1);
+			expect(actualReadings[groupA.id][0].start_timestamp.isSame(startTimestamp)).to.equal(true);
+			expect(actualReadings[groupA.id][0].end_timestamp.isSame(endTimestamp)).to.equal(true);
+			expect(actualReadings[groupA.id][0].reading_rate).to.equal(readingValue);
+		});
+		mocha.it('can get readings from a group containing groups containing meters', async () => {
+			const groupC = await Group.getByName('C');
+			const actualReadings = await Reading.getCompressedGroupReadings([groupC.id], null, null, 1);
+			expect(actualReadings[groupC.id]).to.have.lengthOf(1);
+			expect(actualReadings[groupC.id][0].start_timestamp.isSame(startTimestamp)).to.equal(true);
+			expect(actualReadings[groupC.id][0].end_timestamp.isSame(endTimestamp)).to.equal(true);
+			expect(actualReadings[groupC.id][0].reading_rate).to.equal(readingValue * 2);
+		});
+	});
 });