diff --git a/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTracker.java b/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTracker.java
index e31569b97..4a427114c 100644
--- a/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTracker.java
+++ b/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTracker.java
@@ -17,93 +17,76 @@
 package com.zaxxer.hikari.metrics.prometheus;
 
 import com.zaxxer.hikari.metrics.IMetricsTracker;
-
 import io.prometheus.client.Collector;
 import io.prometheus.client.CollectorRegistry;
 import io.prometheus.client.Counter;
 import io.prometheus.client.Summary;
+import java.util.concurrent.TimeUnit;
 
 class PrometheusMetricsTracker implements IMetricsTracker
 {
-   private final Counter.Child connectionTimeoutCounter;
-   private final Summary.Child elapsedAcquiredSummary;
-   private final Summary.Child elapsedBorrowedSummary;
-   private final Summary.Child elapsedCreationSummary;
-
-   private final Counter ctCounter;
-   private final Summary eaSummary;
-   private final Summary ebSummary;
-   private final Summary ecSummary;
-
+   private static final Counter CONNECTION_TIMEOUT_COUNTER = Counter.build()
+      .name("hikaricp_connection_timeout_total")
+      .labelNames("pool")
+      .help("Connection timeout total count")
+      .register();
+   private static final Summary ELAPSED_ACQUIRED_SUMMARY = Summary.build()
+      .name("hikaricp_connection_acquired_nanos")
+      .labelNames("pool")
+      .help("Connection acquired time (ns)")
+      .register();
+   private static final Summary ELAPSED_BORROWED_SUMMARY = Summary.build()
+      .name("hikaricp_connection_usage_millis")
+      .labelNames("pool")
+      .help("Connection usage (ms)")
+      .register();
+   private static final Summary ELAPSED_CREATION_SUMMARY = Summary.build()
+      .name("hikaricp_connection_creation_millis")
+      .labelNames("pool")
+      .help("Connection creation (ms)")
+      .register();
+
+   private final Counter.Child connectionTimeoutCounterChild;
+   private final Summary.Child elapsedAcquiredSummaryChild;
+   private final Summary.Child elapsedBorrowedSummaryChild;
+   private final Summary.Child elapsedCreationSummaryChild;
    private final Collector collector;
-   private final CollectorRegistry registry;
 
-   PrometheusMetricsTracker(String poolName, Collector collector, CollectorRegistry registry)
-   {
+   PrometheusMetricsTracker(String poolName, Collector collector) {
       this.collector = collector;
-      this.registry = registry;
-
-      ctCounter = Counter.build()
-         .name("hikaricp_connection_timeout_count")
-         .labelNames("pool")
-         .help("Connection timeout count")
-         .register(registry);
-
-      this.connectionTimeoutCounter = ctCounter.labels(poolName);
-
-      eaSummary = Summary.build()
-         .name("hikaricp_connection_acquired_nanos")
-         .labelNames("pool")
-         .help("Connection acquired time (ns)")
-         .register(registry);
-      this.elapsedAcquiredSummary = eaSummary.labels(poolName);
-
-      ebSummary = Summary.build()
-         .name("hikaricp_connection_usage_millis")
-         .labelNames("pool")
-         .help("Connection usage (ms)")
-         .register(registry);
-      this.elapsedBorrowedSummary = ebSummary.labels(poolName);
-
-      ecSummary = Summary.build()
-            .name("hikaricp_connection_creation_millis")
-            .labelNames("pool")
-            .help("Connection creation (ms)")
-            .register(registry);
-      this.elapsedCreationSummary = ecSummary.labels(poolName);
+      this.connectionTimeoutCounterChild = CONNECTION_TIMEOUT_COUNTER.labels(poolName);
+      this.elapsedAcquiredSummaryChild = ELAPSED_ACQUIRED_SUMMARY.labels(poolName);
+      this.elapsedBorrowedSummaryChild = ELAPSED_BORROWED_SUMMARY.labels(poolName);
+      this.elapsedCreationSummaryChild = ELAPSED_CREATION_SUMMARY.labels(poolName);
    }
 
    @Override
    public void close()
    {
-      registry.unregister(ctCounter);
-      registry.unregister(eaSummary);
-      registry.unregister(ebSummary);
-      registry.unregister(ecSummary);
-      registry.unregister(collector);
+      CollectorRegistry.defaultRegistry.unregister(collector);
    }
 
    @Override
    public void recordConnectionAcquiredNanos(long elapsedAcquiredNanos)
    {
-      elapsedAcquiredSummary.observe(elapsedAcquiredNanos);
+      elapsedAcquiredSummaryChild.observe(elapsedAcquiredNanos);
    }
 
    @Override
    public void recordConnectionUsageMillis(long elapsedBorrowedMillis)
    {
-      elapsedBorrowedSummary.observe(elapsedBorrowedMillis);
+      elapsedBorrowedSummaryChild.observe(elapsedBorrowedMillis);
    }
 
    @Override
    public void recordConnectionCreatedMillis(long connectionCreatedMillis)
    {
-      elapsedCreationSummary.observe(connectionCreatedMillis);
+      elapsedCreationSummaryChild.observe(connectionCreatedMillis);
    }
 
    @Override
    public void recordConnectionTimeout()
    {
-      connectionTimeoutCounter.inc();
+      connectionTimeoutCounterChild.inc();
    }
 }
diff --git a/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerFactory.java b/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerFactory.java
index 1b18e8e5e..62e418120 100644
--- a/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerFactory.java
+++ b/src/main/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerFactory.java
@@ -19,9 +19,7 @@
 import com.zaxxer.hikari.metrics.IMetricsTracker;
 import com.zaxxer.hikari.metrics.MetricsTrackerFactory;
 import com.zaxxer.hikari.metrics.PoolStats;
-
 import io.prometheus.client.Collector;
-import io.prometheus.client.CollectorRegistry;
 
 /**
  * <pre>{@code
@@ -31,20 +29,9 @@
  */
 public class PrometheusMetricsTrackerFactory implements MetricsTrackerFactory
 {
-
-   private final CollectorRegistry registry;
-
-   public PrometheusMetricsTrackerFactory() {
-     this(CollectorRegistry.defaultRegistry);
-   }
-
-   public PrometheusMetricsTrackerFactory(CollectorRegistry registry) {
-      this.registry = registry;
-   }
-
    @Override
    public IMetricsTracker create(String poolName, PoolStats poolStats) {
-      Collector collector = new HikariCPCollector(poolName, poolStats).register(registry);
-      return new PrometheusMetricsTracker(poolName, collector, registry);
+      Collector collector = new HikariCPCollector(poolName, poolStats).register();
+      return new PrometheusMetricsTracker(poolName, collector);
    }
 }
diff --git a/src/test/java/com/zaxxer/hikari/metrics/prometheus/HikariCPCollectorTest.java b/src/test/java/com/zaxxer/hikari/metrics/prometheus/HikariCPCollectorTest.java
index 43be0672d..63746a3d5 100644
--- a/src/test/java/com/zaxxer/hikari/metrics/prometheus/HikariCPCollectorTest.java
+++ b/src/test/java/com/zaxxer/hikari/metrics/prometheus/HikariCPCollectorTest.java
@@ -19,16 +19,17 @@
 import static com.zaxxer.hikari.pool.TestElf.newHikariConfig;
 import static com.zaxxer.hikari.util.UtilityElf.quietlySleep;
 import static org.hamcrest.CoreMatchers.is;
-import static org.hamcrest.CoreMatchers.nullValue;
 import static org.junit.Assert.assertThat;
 
+import java.sql.Connection;
+
+import org.junit.Test;
+
 import com.zaxxer.hikari.HikariConfig;
 import com.zaxxer.hikari.HikariDataSource;
 import com.zaxxer.hikari.mocks.StubConnection;
-import io.prometheus.client.CollectorRegistry;
-import org.junit.Test;
 
-import java.sql.Connection;
+import io.prometheus.client.CollectorRegistry;
 
 public class HikariCPCollectorTest {
    @Test
@@ -116,32 +117,10 @@ public void connectionClosed() throws Exception {
       }
    }
 
-   @Test
-   public void checkRegistry() {
-      HikariConfig config = newHikariConfig();
-      config.setMinimumIdle(0);
-      CollectorRegistry customRegistry = new CollectorRegistry();
-      config.setMetricsTrackerFactory(new PrometheusMetricsTrackerFactory(customRegistry));
-      config.setDataSourceClassName("com.zaxxer.hikari.mocks.StubDataSource");
-
-      StubConnection.slowCreate = true;
-      try (HikariDataSource ds = new HikariDataSource(config)) {
-         assertThat(getValue("hikaricp_active_connections", "checkRegistry", customRegistry), is(0.0));
-         assertThat(getValue("hikaricp_active_connections", "checkRegistry"), is(nullValue()));
-      }
-      finally {
-         StubConnection.slowCreate = false;
-      }
-   }
-
-   private Double getValue(String name, String poolName) {
-     return this.getValue(name, poolName, CollectorRegistry.defaultRegistry);
-   }
-
-   private Double getValue(String name, String poolName, CollectorRegistry registry) {
+   private double getValue(String name, String poolName) {
       String[] labelNames = {"pool"};
       String[] labelValues = {poolName};
-      return registry.getSampleValue(name, labelNames, labelValues);
+      return CollectorRegistry.defaultRegistry.getSampleValue(name, labelNames, labelValues);
    }
 
 }
diff --git a/src/test/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerTest.java b/src/test/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerTest.java
index 39c537dab..da634cc95 100644
--- a/src/test/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerTest.java
+++ b/src/test/java/com/zaxxer/hikari/metrics/prometheus/PrometheusMetricsTrackerTest.java
@@ -19,17 +19,18 @@
 import static com.zaxxer.hikari.pool.TestElf.newHikariConfig;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.is;
-import static org.hamcrest.CoreMatchers.nullValue;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 
+import java.sql.Connection;
+import java.sql.SQLTransientConnectionException;
+
+import org.junit.Test;
+
 import com.zaxxer.hikari.HikariConfig;
 import com.zaxxer.hikari.HikariDataSource;
-import io.prometheus.client.CollectorRegistry;
-import org.junit.Test;
 
-import java.sql.Connection;
-import java.sql.SQLTransientConnectionException;
+import io.prometheus.client.CollectorRegistry;
 
 public class PrometheusMetricsTrackerTest {
 
@@ -46,7 +47,7 @@ public void recordConnectionTimeout() throws Exception {
 
       try (HikariDataSource hikariDataSource = new HikariDataSource(config)) {
          try (Connection connection1 = hikariDataSource.getConnection();
-              Connection connection2 = hikariDataSource.getConnection()) {
+            Connection connection2 = hikariDataSource.getConnection()) {
             try (Connection connection3 = hikariDataSource.getConnection()) {
             }
             catch (SQLTransientConnectionException ignored) {
@@ -54,7 +55,7 @@ public void recordConnectionTimeout() throws Exception {
          }
 
          assertThat(CollectorRegistry.defaultRegistry.getSampleValue(
-            "hikaricp_connection_timeout_count",
+            "hikaricp_connection_timeout_total",
             labelNames,
             labelValues), is(1.0));
          assertThat(CollectorRegistry.defaultRegistry.getSampleValue(
@@ -77,26 +78,37 @@ public void recordConnectionTimeout() throws Exception {
    }
 
    @Test
-   public void testThatTheProperRegistryIsUsed() throws Exception {
+   public void testMultiplePoolName() throws Exception {
+      String[] labelNames = {"pool"};
+
       HikariConfig config = newHikariConfig();
-      CollectorRegistry customRegistry = new CollectorRegistry();
-      config.setMetricsTrackerFactory(new PrometheusMetricsTrackerFactory(customRegistry));
+      config.setMetricsTrackerFactory(new PrometheusMetricsTrackerFactory());
+      config.setPoolName("first");
       config.setJdbcUrl("jdbc:h2:mem:");
       config.setMaximumPoolSize(2);
       config.setConnectionTimeout(250);
+      String[] labelValues1 = {config.getPoolName()};
 
-      String[] labelNames = {"pool"};
-      String[] labelValues = {config.getPoolName()};
-
-      try (HikariDataSource hikariDataSource = new HikariDataSource(config)) {
-         assertThat(customRegistry.getSampleValue(
-            "hikaricp_connection_timeout_count",
+      try (HikariDataSource ignored = new HikariDataSource(config)) {
+         assertThat(CollectorRegistry.defaultRegistry.getSampleValue(
+            "hikaricp_connection_timeout_total",
             labelNames,
-            labelValues), is(0.0));
+            labelValues1), is(0.0));
+      }
+
+      HikariConfig config2 = newHikariConfig();
+      config2.setMetricsTrackerFactory(new PrometheusMetricsTrackerFactory());
+      config2.setPoolName("second");
+      config2.setJdbcUrl("jdbc:h2:mem:");
+      config2.setMaximumPoolSize(4);
+      config2.setConnectionTimeout(250);
+      String[] labelValues2 = {config2.getPoolName()};
+
+      try (HikariDataSource ignored = new HikariDataSource(config2)) {
          assertThat(CollectorRegistry.defaultRegistry.getSampleValue(
-             "hikaricp_connection_usage_millis_sum",
-             labelNames,
-             labelValues), is(nullValue()));
+            "hikaricp_connection_timeout_total",
+            labelNames,
+            labelValues2), is(0.0));
       }
    }
 }