Exhibit 21

SUBSIDIARIES

|Name of Corporation                     |  | Jurisdiction       
|--------------------------------------- |  | -------------------
|1167201 Ontario Limited                 |  | Canada             
|A & M Cleaning Products, LLC            |  | Delaware/U.S.      
|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.S.                    |  | 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        
|GLCC Laurel, LLC                        |  | Delaware/U.S.      
|GLCC Laurel de Mexico, S.A. de C.V.     |  | Mexico             
|GLCC Mexico Holdings, Inc.              |  | Delaware/U.S.      
|GLK Holdings (Netherlands) C.V.         |  | The Netherlands    
|GLK Services, Inc.                      |  | Delaware/U.S.      
|Great Lakes (UK) Limited                |  | United Kingdom     
|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 France SAS         |  | France             
|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        
|                                        |  |                    

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|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 Sales Mexico, S. de R.L. de C.V. |  | Mexico        
|Great Lakes SAS                              |  | France        
|Great Lakes Technology (Belgium) N.V.        |  | Belgium       
|Great Lakes Trading Company, Inc.            |  | Delaware/U.S. 
|Gulf Stabilizers Industries Sales FZCO       |  | Dubai         
|Gulf Stabilizers Industries, Ltd.            |  | Saudi Arabia  
|HomeCare Labs, Inc.                          |  | Delaware/U.S. 
|Hydrotech Chemical Corporation               |  | Canada        
|Hydrotech Chemical Corporation Pty. Ltd      |  | Australia     
|INTERBAYROL, A.G.                            |  | Switzerland   
|ISCI, Inc.                                   |  | Indiana/U.S.  
|MPC S.A.R.L.                                 |  | 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        
|TETRABROM Technologies Ltd.                  |  | Israel        
|WRL of Indiana, Inc.                         |  | Indiana/U.S.  

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