ALTER TABLE tanks
    ADD CONSTRAINT fk_tanks_tankGroup
    FOREIGN KEY (tankGroupID)
    REFERENCES tankGroups(tankGroupID)
    ON DELETE CASCADE
    ON UPDATE CASCADE;

ALTER TABLE tanks
    ADD CONSTRAINT fk_tanks_tankSize
    FOREIGN KEY (tankSizeID)
    REFERENCES tankSizes(tankSizeID)
    ON DELETE CASCADE
    ON UPDATE CASCADE;

ALTER TABLE tanks
    ADD CONSTRAINT fk_tanks_thermometer
    FOREIGN KEY (thermometerID)
    REFERENCES thermometers(thermometerID)
    ON DELETE CASCADE
    ON UPDATE CASCADE;

ALTER TABLE tanks
    ADD CONSTRAINT fk_tanks_heater
    FOREIGN KEY (heaterID)
    REFERENCES heaters(heaterID)
    ON DELETE CASCADE
    ON UPDATE CASCADE;
