Exhibit 21

SUBSIDIARIES

|Name of Corporation                                      |  | Jurisdiction       
|-------------------------------------------------------- |  | -------------------
|1167201 Ontario Limited                                  |  | Canada             
|Antimony Products (Proprietary) Ltd.                     |  | South Africa       
|Aqua Clear Industries, L.L.C.                            |  | New York/U.S.      
|ASCK, Inc.                                               |  | Delaware/U.S.      
|ASEPSIS, Inc.                                            |  | Canada             
|ASEPSIS, Inc.                                            |  | Georgia/U.S.       
|ASIA Stabilizers Co., Ltd.                               |  | Korea              
|BAYROL Deutschland GmbH                                  |  | Germany            
|BAYROL FRANCE S.A.                                       |  | France             
|BAYROL Iberica S.A.                                      |  | Spain              
|Bio-Lab Canada, Inc.                                     |  | Canada             
|Bio-Lab, Inc.                                            |  | Delaware/U.S.      
|BioLab (Gulf) GmbH                                       |  | Switzerland        
|BioLab Arabia Limited                                    |  | Saudi Arabia       
|BioLab Australia Pty. Ltd.                               |  | Australia          
|Biolab Services, Inc.                                    |  | Delaware/U.S.      
|BioLab Textile Additives, LLC                            |  | Delaware/U.S.      
|BioLab U.K. Limited                                      |  | United Kingdom     
|BLSA Industries (Pty) Ltd                                |  | South Africa       
|Blue Systemes S.A.S.                                     |  | France             
|Chemol France S.A.                                       |  | France             
|Chemol Reszvenytarsasag International                    |  | Hungary            
|GL Development, Ltd.                                     |  | British West Indies
|GLC Holdings GmbH                                        |  | Switzerland        
|GLK Holdings (Netherlands) B.V.                          |  | The Netherlands    
|GLK Services, Inc.                                       |  | Delaware/U.S.      
|Great Lakes (UK) Limited                                 |  | United Kingdom     
|Great Lakes Chemical (Barbados) Limited                  |  | Barbados           
|Great Lakes Chemical (Europe) GmbH                       |  | Switzerland        
|Great Lakes Chemical (Far East) Limited                  |  | Hong Kong          
|Great Lakes Chemical (Gulf) GmbH                         |  | Switzerland        
|Great Lakes Chemical (Netherlands) B.V.                  |  | The Netherlands    
|Great Lakes Chemical (S) Pte Ltd.                        |  | Singapore          
|Great Lakes Chemical Corporation de Mexico, S.A. de C.V. |  | Mexico             
|Great Lakes Chemical France SAS                          |  | France             
|                                                         |  |                    

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|Great Lakes Chemical Global, Inc.        |  | Delaware/U.S. 
|---------------------------------------- |  | --------------
|Great Lakes Chemical Japan Limited       |  | Japan         
|Great Lakes Chemical Konstanz GmbH       |  | Germany       
|Great Lakes Europe Unlimited             |  | United Kingdom
|Great Lakes Holding (Europe) AG          |  | Switzerland   
|Great Lakes Holding Deutschland GmbH     |  | Germany       
|Great Lakes Holding SAS                  |  | France        
|Great Lakes Manufacturing (Germany) GmbH |  | Germany       
|Great Lakes Manufacturing (UK) Limited   |  | United Kingdom
|Great Lakes Manufacturing Italy S.r.l.   |  | Italy         
|Great Lakes Sales (Europe) GmbH          |  | Switzerland   
|Great Lakes Sales (Germany) GmbH         |  | Germany       
|Great Lakes Sales (UK) Limited           |  | United Kingdom
|Great Lakes Sales France SAS             |  | France        
|Great Lakes Sales Italy S.r.l.           |  | Italy         
|Great Lakes SAS                          |  | France        
|Great Lakes Technology (Belgium) N.V.    |  | Belgium       
|Great Lakes Technology Italy Srl         |  | Italy         
|Great Lakes Trading Company, Inc.        |  | Delaware/U.S. 
|Gulf Stabilizers Industries Sales FZCO   |  | Dubai         
|Gulf Stabilizers Industries, Ltd.        |  | Saudi Arabia  
|Hydrotech Chemical Corporation           |  | Canada        
|Hydrotech Chemical Corporation Pty. Ltd  |  | Australia     
|INTERBAYROL, A.G.                        |  | Switzerland   
|ISCI, Inc.                               |  | Indiana/U.S.  
|MPC S.A.S.                               |  | France        
|Niagara Insurance Company, Ltd           |  | Bermuda       
|PABU Services, Inc.                      |  | Delaware/U.S. 
|PCBU Services, Inc.                      |  | Delaware/U.S. 
|Poolbrite (SA) (PTY) Ltd                 |  | South Africa  
|POOLTIME GmbH                            |  | Germany       
|QO Chemicals GmbH                        |  | Germany       
|QO Chemicals Inc.                        |  | Delaware/U.S. 
|Recreational Water Products, Inc.        |  | Delaware/U.S. 
|Recreational Water Products Pty. Ltd.    |  | Australia     
|Recreational Water Products Inc.         |  | Canada        
|WIL Research Laboratories, Inc.          |  | Indiana/U.S.  

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