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                                                                    EXHIBIT 31.2

                            CERTIFICATION PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

        I, Robert E. McCray, Chief Financial Officer of Sionix Corporation,
Inc., certify that:

              1. I have reviewed this annual report on Form 10-KSB of Sionix
        Corporation for the year ended September 30, 2006;

              2. Based on my knowledge, this report does not contain any untrue
        statement of a material fact or omit to state a material fact necessary
        to make the statements made, in light of the circumstances under which
        such statements were made, not misleading with respect to the period
        covered by this report;

              3. Based on my knowledge, the financial statements, and other
        financial information included in this report, fairly present in all
        material respects the financial condition, results of operations and
        cash flows of the registrant as of, and for, the periods presented in
        this report;

              4. The registrant's other certifying officer and I are responsible
        for establishing and maintaining disclosure controls and procedures (as
        defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
        registrant and have:

                    (a) Designed such disclosure controls and procedures, or
              caused such disclosure controls and procedures to be designed
              under our supervision, to ensure that material information
              relating to the registrant, including its consolidated
              subsidiaries, is made known to us by others within those entities,
              particularly during the period in which this report is being
              prepared;

                    (b) Evaluated the effectiveness of the registrant's
              disclosure controls and procedures and presented in this report
              our conclusions about the effectiveness of the disclosure controls
              and procedures as of the end of the period covered by this report
              based on such evaluation; and

                    (c) Disclosed in this report any change in the registrant's
              internal control over financial reporting that occurred during the
              registrant's most recent fiscal quarter that has materially
              affected, or is reasonably likely to materially affect, the
              registrant's internal control over financial reporting.

              5. The registrant's other certifying officer and I have disclosed,
        based on our most recent evaluation, to the registrant's auditors and
        the audit committee of registrant's board of directors (or persons
        performing the equivalent functions):

                    (a) All significant deficiencies and material weaknesses in
              the design or operation of internal control over financial
              reporting which are reasonably likely to adversely affect the
              registrant's ability to record, process, summarize and report
              financial information; and

                    (b) Any fraud, whether or not material, that involves
              management or other employees who have a significant role in the
              registrant's internal control over financial reporting.

Date: June 8, 2007                                      /s/ Robert E. McCray
                                                        -----------------------
                                                        Robert E. McCray
                                                        Chief Financial Officer