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                                                                     EXHIBIT 5.1



            [Letterhead of Skadden, Arps, Slate, Meagher & Flom LLP]


                                 April 13, 2000


Electropure, Inc.
23456 South Pointe
Laguna Hills, California  92653

                      Re:    Electropure, Inc.
                             Registration on Form S-8, Registration 333-

Ladies and Gentlemen:

               We have acted as special counsel to Electropure, Inc., a
California corporation (the "Company"), in connection with the potential
issuance of 1,000,0000 shares (the "Shares") of the Company's Common Stock, par
value $0.01 per share (the "Common Stock") pursuant to options granted or which
may be granted under the Company's 1999 Stock Option Plan (the "Plan").

               This opinion is being furnished in accordance with the
requirements of Item 601(b)(5) of Regulation S-B under the Securities Act of
1933, as amended (the "Act").

               In connection with this opinion, we have examined originals or
copies, certified or otherwise identified to our satisfaction, of (i) the
Registration Statement on Form S-8 (File No. 333-_______) as filed with the
Securities and Exchange Commission (the "Commission") on April 14, 2000 under
the Act, (such Registration Statement, as so amended, being hereinafter referred
to as the "Registration Statement"); (ii) a specimen certificate representing
the Common Stock; (iii) the Articles of Incorporation of the Company, as
presently in effect; (iv) the By-Laws of the Company, as presently in effect;
and (v) certain resolutions of the Board of Directors and Shareholders of the
Company relating to the adoption of the Plan and the form of options to be


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granted under the Plan. We have also examined originals or copies, certified or
otherwise identified to our satisfaction, of such records of the Company and
such agreements, certificates of public officials, certificates of officers or
other representatives of the Company and others, and such other documents,
certificates and records as we have deemed necessary or appropriate as a basis
for the opinions set forth herein.

               In our examination, we have assumed the legal capacity of all
natural persons, the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified, conformed or photostatic copies and
the authenticity of the originals of such latter documents. In making our
examination of documents executed or to be executed by parties other than the
Company, we have assumed that such parties had or will have the power, corporate
or other, to enter into and perform all obligations thereunder and have also
assumed the due authorization by all requisite action, corporate or other, and
execution and delivery by such parties of such documents and the validity and
binding effect thereof. As to any facts material to the opinions expressed
herein which we have not independently established or verified, we have relied
upon statements and representations of officers and other representatives of the
Company and others.

               Members of our firm are admitted to the bar in the State of
California and we do not express any opinion as to the laws of any other
jurisdiction.

               Based upon and subject to the foregoing, we are of the opinion
that when the Registration Statement becomes effective, upon exercise of options
granted under the Plan in accordance with their respective terms, the issuance
and sale of such Shares will have been duly authorized, and the Shares will be
validly issued, fully paid and nonassessable.

               We hereby consent to the filing of this opinion with the
Commission as an exhibit to the Registration Statement. We also consent to the
reference to our firm under the caption "Legal Matters" in the Registration
Statement. In giving this consent, we do not thereby admit that we are included
in the category of persons whose consent is required under Section 7 of the Act
or the rules and regulations of the Commission.

                                            Very truly yours,


                                   [Skadden, Arps, Slate, Meagher & Flom]