Supplement to Prospectus Dated May 1, 2000

                       Supplement dated September 25, 2000

This Supplement should be retained with the current Prospectus for your variable
annuity  contract  issued  by  American   Skandia  Life  Assurance   Corporation
("American  Skandia").  If you do not have a current  prospectus  please contact
American Skandia at 1-800-SKANDIA.

                            A. PROPOSED SUBSTITUTION

American  Skandia has filed an  application  with the  Securities  and  Exchange
Commission ("SEC") to substitute the following "Replaced  Portfolio/Sub-account"
with the "Substitute Portfolio/Sub-account":



- --------------------------------------------------------- ---------- ---------------------------------------------------------------
             REPLACED PORTFOLIO/SUB-ACCOUNT                                         SUBSTITUTE PORTFOLIO/SUB-ACCOUNT
- --------------------------------------------------------- ---------- ---------------------------------------------------------------
- --------------------------------------------------------------- -------- -----------------------------------------------------------
                                                                      
Alger American MidCap Growth portfolio of The Alger American             AST Alger Mid-Cap Growth portfolio of American Skandia
Fund/AA MidCap Growth Sub-account                                        Trust/AST Alger Mid-Cap Growth Sub-account
- --------------------------------------------------------------- -------- -----------------------------------------------------------


As part of the  Substitution,  American  Skandia is seeking  permission to allow
transfers  from  the  Replaced  Portfolio/Sub-account  to any  other  investment
options available under the Annuity for a period beginning from the date of this
Supplement  without the imposition of any transfer fee.  Additionally,  American
Skandia Life Assurance  Corporation  will not exercise any rights reserved under
the Annuity to impose  additional  restrictions  on transfers  until at least 30
days after the Substitution. Under the proposed substitution, any such transfers
would not count in determining  whether the maximum number of free transfers has
been exceeded.  Furthermore,  under the proposed  substitution,  the transfer of
Account  Value  from  the  Replaced   Portfolio/Sub-account  to  the  Substitute
Portfolio/Sub-account  would likewise not be subject to a transfer fee nor count
in determining  whether the maximum number of free transfers have been exceeded.
The proposed  substitution  will not affect your rights or our obligations under
the Annuity.  American  Skandia will bear any  expenses in  connection  with the
proposed substitution.

Contract    Owners   with    Account    Value    allocated   to   the   Replaced
Portfolio/Sub-account  may remain in the Sub-account until the earliest to occur
of:   (1)  the  date  they   transfer   Account   Value  out  of  the   Replaced
Portfolio/Sub-account;  or (2) the date the proposed  substitution is completed.
On or after the date of the  substitution,  the  Replaced  Portfolio/Sub-account
will no longer exist. Contract Owners will no longer be able to allocate Account
Value to the Replaced Portfolio/Sub-account after the substitution date.

                      B. INVESTMENT OBJECTIVES AND POLICIES

A short  description  of the  investment  objective  (in  italics)  and a short,
summary  description of the key policies for the Substitute  Portfolio  follows.
The AST  Alger  Mid-Cap  Growth  portfolio  of  American  Skandia  Trust  is not
currently available;  however, it will be available at the time the Substitution
is effective.



- ------------------- ---------------------------------------------------------------------------------------- -----------------------
                                                                                                           PORTFOLIO
      STYLE/                       INVESTMENT OBJECTIVES/POLICIES                                          ADVISOR/
       TYPE                                                                                                SUB-ADVISOR
- ------------------- ------------------------------------------------------------------------------------------------ ---------------
- ------------------- ------------------------------------------------------------------------------------------------ ---------------
                                                                                                    

                  AST Alger Mid-Cap Growth:  seeks long-term capital growth. The                          Fred Alger
                  Portfolio  invests  primarily  in equity  securities,  such as                          Management, Inc.
                  common or preferred stocks,  that are listed on U.S. exchanges
                  or in the over-the-counter market. Under normal circumstances,
 MID CAP          the Portfolio  invests  primarily in the equity  securities of
 GROWTH           companies having a market  capitalization  within the range of
                  companies  in the S&P  MidCap  400 Index.  The  Portfolio  may
                  invest up to 35% of its total  assets  in equity  security  of
                  companies  that,  at the time of  purchase,  have total market
                  capitalization  outside  the  range  of  companies  in the S&P
                  MidCap  400 Index and in excess of that  amount (up to 100% of
                  its assets) during temporary defensive periods.

- ------------------- ------------------------------------------------------------------------------------------------ ---------------

GAL3 - SUPP. (09/25/2000)