diff --git a/tests/database/database_selector.cpp b/tests/database/database_selector.cpp
index 07f7bb7..9f013a1 100644
--- a/tests/database/database_selector.cpp
+++ b/tests/database/database_selector.cpp
@@ -1,120 +1,124 @@
 #include "catch.hpp"
 
 #include "database/yaml_reader.hpp"
 #include "database/selector.hpp"
 #include "database/mineral_selector.hpp"
 #include "str_database.hpp"
 #include "utils/timer.hpp"
 
 #include <iostream>
 #include <sstream>
 
 using namespace specmicp;
 using namespace specmicp::database;
 
 TEST_CASE("DatabaseSelector", "[Database, Component]")
 {
     std::istringstream input(good_test_database);
     DataReaderYaml reader(input);
 
     auto data = reader.get_database();
 
     SECTION("Remove a component")
     {
         Timer timer;
         DatabaseSelector selector(data);
         selector.remove_component({data->components.get_id("C3")});
         timer.stop();
         std::cout << "Removing a component : " << timer.elapsed_time()*1000 << " ms (Ref 0.010ms)" << std::endl;
 
         CHECK(data->components.is_valid());
         CHECK(data->aqueous.is_valid());
         CHECK(data->minerals.is_valid());
         CHECK(data->minerals_kinetic.is_valid());
         CHECK(data->gas.is_valid());
         CHECK(data->is_valid());
 
         // basis
         CHECK(data->nb_component() == 4);
         CHECK(data->components.get_id("C3") == no_species);
 
         // aqueous
         CHECK(data->nb_aqueous() == 2);
         CHECK(data->aqueous.get_id("A3") == no_species);
 
         // minerals
         CHECK(data->nb_mineral() == 1);
         CHECK(data->minerals.get_id("M2") == no_species);
 
         // minerals_kinetic
         CHECK(data->nb_mineral_kinetic() == 0);
         CHECK(data->minerals_kinetic.get_id("MK1") == no_species);
 
         // Gas
         CHECK(data->nb_gas() == 0);
         CHECK(data->gas.get_id("G1") == no_species);
 
         // Sorbed
         CHECK(data->nb_sorbed() == 0);
         CHECK(data->sorbed.get_id("S1") == no_species);
 
+        // compound
+        CHECK(data->nb_compounds() == 0);
+        CHECK(data->compounds.get_id("Comp1") == no_species);
+
         // Element
         CHECK(data->get_id_component_from_element("C3") == no_species);
         CHECK(data->get_label_component_from_element("C1") == "C1[-]");
         CHECK(data->get_label_component_from_element("C2") == "C2[+]");
     }
 }
 
 TEST_CASE("MineralSelector", "[Select,minerals]")
 {
     std::istringstream input(good_test_database);
     auto data = DataReaderYaml(input).get_database();
 
     SECTION("Mineral selector") {
         size_t orig_hash = data->get_hash();
 
         MineralSelector(data).keep_only({"M1"});
 
         CHECK(data->minerals.is_valid());
         CHECK(data->minerals_kinetic.is_valid());
         CHECK(data->is_valid());
         CHECK(data->get_hash() != orig_hash);
 
 
         // Mineral
         // -------
 
         CHECK(data->nb_mineral() == 1);
         CHECK(data->minerals.get_id("M2") == no_species);
 
         CHECK(data->nu_mineral(0, 0) == 0.0);
         CHECK(data->nu_mineral(0, 1) == 0.0);
         CHECK(data->nu_mineral(0, 2) == 1.0);
         CHECK(data->nu_mineral(0, 3) == 1.0);
         CHECK(data->nu_mineral(0, 4) == 0.0);
         CHECK(data->logk_mineral(0) == -7);
         CHECK(data->molar_volume_mineral(0) == 1e-6*10.0);
 
         // Mineral kinetic
         // ---------------
 
         CHECK(data->nb_mineral_kinetic() == 2);
         CHECK(data->minerals_kinetic.get_id("M2") == 1);
 
         CHECK(data->nu_mineral_kinetic(0, 0) == 0.0);
         CHECK(data->nu_mineral_kinetic(0, 1) == 0.0);
         CHECK(data->nu_mineral_kinetic(0, 2) == 1.0);
         CHECK(data->nu_mineral_kinetic(0, 3) == 1.0);
         CHECK(data->nu_mineral_kinetic(0, 4) == 2.0);
         CHECK(data->logk_mineral_kinetic(0) == -9);
         CHECK(data->molar_volume_mineral_kinetic(0) == 1e-6*30.0);
 
         CHECK(data->nu_mineral_kinetic(1, 0) == 0.0);
         CHECK(data->nu_mineral_kinetic(1, 1) == 0.0);
         CHECK(data->nu_mineral_kinetic(1, 2) == 2.0);
         CHECK(data->nu_mineral_kinetic(1, 3) == 2.0);
         CHECK(data->nu_mineral_kinetic(1, 4) == 1.0);
         CHECK(data->logk_mineral_kinetic(1) == -6+data->logk_aqueous(1)+data->logk_aqueous(2));
         CHECK(data->unsafe_molar_volume_mineral_kinetic(1) < 0);
     }
 }
diff --git a/tests/database/database_switch.cpp b/tests/database/database_switch.cpp
index 45421f3..28d3a4c 100644
--- a/tests/database/database_switch.cpp
+++ b/tests/database/database_switch.cpp
@@ -1,112 +1,123 @@
 #include "catch.hpp"
 
 #include "database/yaml_reader.hpp"
 #include "database/switch_basis.hpp"
 #include "str_database.hpp"
 
 #include "utils/timer.hpp"
 
 #include <iostream>
 #include <sstream>
 
 using namespace specmicp;
 using namespace specmicp::database;
 
 TEST_CASE("Switch basis")
 {
     std::istringstream input(good_test_database);
     DataReaderYaml reader(input);
 
     auto data = reader.get_database();
 
     SECTION("switch basis") {
         size_t orig_hash = data->get_hash();
 
         Timer timer;
         BasisSwitcher switcher(data);
         std::map<std::string, std::string> swapping = {{"C3", "A3[-]"}};
         switcher.swap_components(swapping);
         timer.stop();
 
         std::cout << "Switching basis : " << timer.elapsed_time()*1000 << " ms (Ref 0.020ms)" << std::endl;
 
         CHECK(data->components.is_valid());
         CHECK(data->aqueous.is_valid());
         CHECK(data->minerals.is_valid());
         CHECK(data->minerals_kinetic.is_valid());
         CHECK(data->is_valid());
 
         CHECK(data->get_hash() != orig_hash);
 
         // Basis
         CHECK(data->nb_component() == 5);
         CHECK(data->components.get_id("C3") == no_species);
         CHECK(data->components.get_id("A3[-]") == 4);
 
         // Aqueous
         CHECK(data->nb_aqueous() == 3);
         CHECK(data->aqueous.get_id("A3[-]") == no_species);
         CHECK(data->aqueous.get_id("C3") == 2);
 
         CHECK(data->nu_aqueous(2, 0) == 0.0);
         CHECK(data->nu_aqueous(2, 1) == 0.0);
         CHECK(data->nu_aqueous(2, 2) == -1.0);
         CHECK(data->nu_aqueous(2, 3) == 0.0);
         CHECK(data->nu_aqueous(2, 4) == 1.0);
         CHECK(data->logk_aqueous(2) == 2.0);
 
         // Mineral
         CHECK(data->nb_mineral() == 2);
 
         CHECK(data->nu_mineral(1, 0) == 0.0);
         CHECK(data->nu_mineral(1, 1) == 0.0);
         CHECK(data->nu_mineral(1, 2) == 1.0);
         CHECK(data->nu_mineral(1, 3) == 2.0);
         CHECK(data->nu_mineral(1, 4) == 1.0);
         CHECK(data->logk_mineral(1) == -10.0);
         CHECK(data->unsafe_molar_volume_mineral(1) < 0);
 
         CHECK(data->molar_mass_mineral(0, units::MassUnit::gram) == 5.0);
 
         // Kinetic mineral
         CHECK(data->nb_mineral_kinetic() == 1);
 
 
         CHECK(data->nu_mineral_kinetic(0, 0) == 0.0);
         CHECK(data->nu_mineral_kinetic(0, 1) == 0.0);
         CHECK(data->nu_mineral_kinetic(0, 2) == -1.0);
         CHECK(data->nu_mineral_kinetic(0, 3) == 1.0);
         CHECK(data->nu_mineral_kinetic(0, 4) == 2.0);
         CHECK(data->logk_mineral_kinetic(0) == -5.0);
         CHECK(data->molar_volume_mineral_kinetic(0) == 1e-6*30.0);
         CHECK(data->molar_mass_mineral_kinetic(0, units::MassUnit::gram) == 13.0);
 
         // gas
         CHECK(data->nb_gas() == 1);
 
         CHECK(data->nu_gas(0, 0) == 0.0);
         CHECK(data->nu_gas(0, 1) == 0.0);
         CHECK(data->nu_gas(0, 2) == -1.0);
         CHECK(data->nu_gas(0, 3) == 0.0);
         CHECK(data->nu_gas(0, 4) == 1.0);
         CHECK(data->logk_gas(0) == 5.0);
 
         // Sorbed
         CHECK(data->nb_sorbed() == 1);
         CHECK(data->sorbed.get_label(0) == "S1");
 
         CHECK(data->nu_sorbed(0, 0) == 0.0);
         CHECK(data->nu_sorbed(0, 1) == 0.0);
         CHECK(data->nu_sorbed(0, 2) == -1.0);
         CHECK(data->nu_sorbed(0, 3) == 0.0);
         CHECK(data->nu_sorbed(0, 4) == 1.0);
         CHECK(data->logk_sorbed(0) == -4);
 
+        // compounds
+        CHECK(data->nb_compounds() == 1);
+        CHECK(data->compounds.get_label(0) == "Comp1");
+
+        CHECK(data->nu_compound(0, 0) == 2.0);
+        CHECK(data->nu_compound(0, 1) == 0.0);
+        CHECK(data->nu_compound(0, 2) == -1.0);
+        CHECK(data->nu_compound(0, 3) == 0.0);
+        CHECK(data->nu_compound(0, 4) == 1.0);
+
+
         // Element
         CHECK(data->get_id_component_from_element("plop") == -1);
         CHECK(data->get_id_component_from_element("C1") != -1);
         CHECK(data->get_label_component_from_element("C1") == "C1[-]");
         CHECK(data->get_label_component_from_element("C3") == "A3[-]");
 
     }
 }