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ESSEF CORPORATION                                                    EXHIBIT 11

Computation of Per Share Earnings                                  
                                                                   
The computation of simple earnings per share and primary earnings per share is
as follows:                                                        
                                                                   
<TABLE>                                                                       
<CAPTION>                                                                     
                                                      Three Months Ended                                       
                                                          December 31                                             
                                                    1995               1994                                   
                                                 ----------        ------------                               
<S>                                              <C>                <C>                                                           
Average shares outstanding for                                                                                                    
computation of simple earnings                                                                                                    
per share                                        5,183,259          4,868,950                                                     
                                                                                                                                  
Add equivalent shares for un-                                       
exercised options at end of                                   
period (a)                                         892,834            877,298                                                     
                                                 ---------          ---------                                                     
                                                                                                                                  
Average shares outstanding for                                                                                                    
computation of primary earnings                                                                                                   
per share                                        6,076,093          5,746,248                                                     
                                                ==========          =========                                                     
                                                                                                                                  
                                                                                                                                  
Earnings per common share:                           $0.17              $0.18                                                       
                                                                                                                                  
                                                                                                                                  
Primary earnings per common                                                                                                       
share:                                               $0.15              $0.16                                                       
</TABLE>                                                                      
                                                                              

(a) Computed under the "Treasury Stock Method" using the average market price 
    for the respective period.          
                                                                             
                                                                             
                                                                             
                                                                             
                                                                             
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