Exhibit 10.1

                    FOURTH AMENDMENT TO AMENDED AND RESTATED
                           REVOLVING CREDIT AGREEMENT


            THIS FOURTH  AMENDMENT  TO AMENDED  AND  RESTATED  REVOLVING  CREDIT
AGREEMENT  (this  "Amendment")  made as of September 28, 2000 by and among NUCO2
INC., a Florida  corporation (the  "Company"),  SUNTRUST BANK, a Georgia banking
corporation (formerly named SunTrust Bank, South Florida,  National Association,
a  national  banking  association)  ("SunTrust"),   BANK  AUSTRIA  CREDITANSTALT
CORPORATE FINANCE, INC., a Delaware corporation (the "Documentation Agent"), THE
PROVIDENT BANK, an Ohio banking  corporation,  BANK LEUMI LE-ISRAEL B.M.,  Miami
Agency,  IBJ WHITEHALL  BUSINESS  CREDIT  CORPORATION,  a New York  corporation,
HAMILTON  BANK,  N.A., a national  banking  association,  and any other banks or
other  lending  institutions  that  are or will  become  parties  to the  Credit
Agreement (as defined below) (collectively, the "Lenders" and each individually,
a "Lender"),  and SUNTRUST BANK, a Georgia banking  corporation  (formerly named
SunTrust  Bank,  South  Florida,   National  Association,   a  national  banking
association), as agent for the Lenders.


                             PRELIMINARY STATEMENTS:

            The  Company,  Agent and the  Lenders  are  parties to that  certain
Amended and Restated  Revolving  Credit  Agreement  dated as of May 4, 1999,  as
amended by that certain First Amendment to Amended and Restated Revolving Credit
Agreement  dated  as of June 16,  1999 and as  amended  by that  certain  Second
Amendment and Waiver to Amended and Restated Revolving Credit Agreement dated as
of February 7, 2000, as amended by that Third  Amendment to Amended and Restated
Revolving  Credit  Agreement dated as of May 12, 2000, (the "Credit  Agreement";
capitalized  terms used herein and not defined  herein  shall have the  meanings
assigned to them in the Credit  Agreement),  pursuant to which the Lenders  made
and continue to make certain financial accommodations to the Company;

            The Company has requested,  and the Lenders have agreed,  to amend a
financial covenant and to make certain other amendments on the terms and subject
to the conditions set forth herein.

            NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged,  the parties hereto,  intending to
be legally bound, agree as follows:

1.          Amendment to Credit Agreement.

            a.  Section 1.01 of the Credit  Agreement  is hereby  amended by (i)
adding the following new definition in proper alphabetical order:



<PAGE>


                         "New Preferred  Stock" shall have the meaning set forth
in Section 7.04.

            (ii)  replacing the  definition of  "Consolidated  Net Worth" in its
entirety with the following:

                         "Consolidated  Net Worth" shall mean, as of the date of
            determination,   the  sum  of,   without   duplication,   (a)  total
            shareholders'  equity  of the  Company  and  its  Subsidiaries  on a
            consolidated  basis  determined in accordance  with GAAP, (b) the 8%
            Convertible Preferred Stock and (c) the New Preferred Stock.

            (iii)   replacing   the  last   sentence   of  the   definition   of
"Indebtedness" in its entirety with the following:

            "Notwithstanding  the foregoing,  Indebtedness  shall exclude the 8%
            Convertible Preferred Stock and the New Preferred Stock."


            b.  Section  7.04 of the  Credit  Agreement  is  hereby  amended  by
replacing such Section 7.04 in its entirety with the following:

                        "SECTION  7.04 Minimum Net Worth.  The Company  shall at
            all times maintain its Consolidated Net Worth greater than a Minimum
            Net Worth,  equal to (i) $37,600,000,  plus (ii) fifty percent (50%)
            of the  cumulative  Consolidated  Net Income for each fiscal quarter
            beginning   after  the  fiscal  quarter  ending  on  June  30,  2000
            (specifically not including any Consolidated Net Loss for any fiscal
            quarter),  plus  (iii) the  cumulative  net  proceeds  of all equity
            offerings,   except  for  the  8%   Convertible   Preferred   Stock.
            Notwithstanding  anything to the contrary in the foregoing sentence,
            the Company shall at all times maintain its  Consolidated  Net Worth
            greater  than a Minimum Net Worth,  equal to (i)  $40,000,000,  plus
            (ii) fifty percent (50%) of the cumulative  Consolidated  Net Income
            for each fiscal quarter beginning after the fiscal quarter ending on
            June 30, 2000  (specifically not including any Consolidated Net Loss
            for any fiscal  quarter),  plus (iii) the cumulative net proceeds of
            all equity offerings,  except for the 8% Convertible Preferred Stock
            and except for an  additional  issuance of preferred  stock of up to
            $10,000,000 (the "New Preferred  Stock"),  provided,  however,  that
            such New  Preferred  Stock is issued on or before  January  31, 2001
            and,  provided  further,  that the definitions of "Consolidated  Net
            Worth"  and  "Indebtedness"  and  Section  8.09  (c) in  the  Senior
            Subordinated  Note  Purchase  Agreement  are amended  upon terms and
            conditions satisfactory in all respects to the Required Lenders.


2.          Conditions  Precedent.  This Amendment  shall become  effective upon
satisfaction of the following conditions:

            a.  The  Agent  shall  have  received  one  or  more  duly  executed
counterparts of this Amendment signed by each of the parties hereto.



<PAGE>

            b. The Agent shall have received such other  documents as any Lender
may reasonably request.


3.          Other Agreements.

            a. The Company hereby affirms that each of the  representations  and
warranties  of the Company  contained in the Credit  Agreement  and in any other
Loan Documents  (except to the extent that any such  representation  or warranty
expressly relates solely to an earlier date and for changes therein permitted or
contemplated by the Credit Agreement) is correct in all material respects on and
as of the date hereof and after giving  effect to this  Amendment.  In addition,
with  respect  to this  Amendment,  Company  warrants  and  represents  that the
execution,  delivery and performance by Company of this Amendment (i) are within
the Company's  corporate power;  (ii) have been duly authorized by all necessary
or proper corporate  action;  (iii) are not in contravention of any provision of
the Company's  certificate of incorporation or bylaws; (iv) will not violate any
law or regulation,  or any order or decree of any  Governmental  Authority;  (v)
will not conflict with or result in the breach or termination  of,  constitute a
default  under  or  accelerate  any  performance  required  by,  any  indenture,
mortgage,  deed of trust,  lease,  agreement  or other  instrument  to which the
Company is a party or by which the Company or any of its property is bound; (vi)
will not  result  in the  creation  or  imposition  of any Lien  upon any of the
property of the  Company  other than those in favor of the Agent for the benefit
of the Lenders, all pursuant to the Loan Documents; and (vii) do not require the
consent or approval of any Governmental  Authority.  Company further  represents
and warrants  that this  Amendment  has been duly executed and delivered for the
benefit  of or on behalf  of the  Company  and  constitutes  a legal,  valid and
binding obligation of the Company, enforceable against the Company in accordance
with its terms.

            b. As  amended  hereby,  all terms of the Credit  Agreement  and the
other  Loan  Documents  shall be and  remain in full  force and effect and shall
constitute the legal, valid, binding and enforceable  obligations of the Company
to the Agent and the  Lenders.  To the  extent any terms and  conditions  in any
other  Loan  Documents  shall  contradict  or be in  conflict  with any terms or
conditions of the Credit Agreement,  after giving effect to this Amendment, such
terms and  conditions  are hereby  deemed  modified and amended  accordingly  to
reflect the terms and conditions of the Credit Agreement as modified and amended
hereby.

            c. The Company  hereby  restates,  ratifies and  reaffirms  each and
every term and  condition  set forth in the Credit  Agreement and the other Loan
Documents,  effective as of the date hereof,  and represents  that, after giving
effect to this  Amendment,  no Default or Event of Default has  occurred  and is
continuing as of the date hereof.

            d. In  connection  with the  preparation,  execution,  delivery  and
enforcement of this Amendment,  the closing hereof,  and any other  transactions
contemplated  hereby,  the Company agrees to pay to the Lenders an amendment fee
equal to .25% of the Commitments  payable in two equal  installments.  The first
installment  shall  be due  and  payable  on the  date  hereof  and  the  second
installment  shall be due and payable on or before  February  1, 2001;  provided
however,




<PAGE>

if the New  Preferred  Stock is issued on or before  January 31, 2001,  then the
Lenders agree to waive payment of the second installment.

            e. The Company agrees to pay on demand all costs and expenses of the
Agent in connection with the preparation, execution, delivery and enforcement of
this Amendment,  the closing  hereof,  and any other  transactions  contemplated
hereby, including the fees and out-of-pocket expenses of the Agent's counsel. In
addition,  the  Company  agrees  to pay all  legal  fees and  expenses  actually
incurred  through  the date  hereof  to the  Agent or  Agent's  counsel,  King &
Spalding, on or before December 10, 2000.

            f. On the date hereof,  the Company shall pay to SunTrust  Equitable
Securities  Corporation  a fee in  accordance  with the  terms  of a fee  letter
between the Company and SunTrust Equitable Securities Corporation.

            g. This  Amendment  may be executed  in any number of  counterparts,
each of which  shall be deemed an  original  and all of which,  taken  together,
shall constitute one and the same instrument.

            h. THIS AMENDMENT  SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH THE INTERNAL LAWS (AND NOT THE LAWS OF CONFLICTS),  OF THE STATE OF FLORIDA
AND ALL APPLICABLE LAWS OF THE UNITED STATES OF AMERICA.

            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly  executed  under  seal  by  their  respective  officers  thereunto  duly
authorized, as of the date first above written.


                                       NUCO2 INC.,
                                       a Florida corporation

                                       By: /s/ Joann Schirripa
                                           --------------------------------
                                           Joann Schirripa
                                           Chief Financial Officer and Treasurer

                                       Attest: /s/ Eric M. Wechsler
                                               ----------------------------
                                               Eric M. Wechsler
                                               General Counsel and Secretary


<PAGE>




                                  SUNTRUST BANK
                                  individually and as Agent

                                  By: /s/ Sandra N. Tozzie
                                      ------------------------
                                      Name: Sandra N. Tozzie
                                      Title: First Vice President




                                  BANK AUSTRIA CREDITANSTALT
                                  CORPORATE FINANCE, INC.,
                                  individually and as Documentation Agent

                                  By:________________________________
                                     Name:
                                     Title:

                                  By:_________________________________
                                     Name:
                                     Title:


                                  BANK-LEUMI LE-ISRAEL B.M.,
                                  MIAMI AGENCY



                                  By: /s/ Stephen Hanas
                                      ---------------------
                                      Stephen Hanas
                                      Vice President


                                  THE PROVIDENT BANK

                                  By: /s/ Nick Jevic
                                      ------------------
                                      Nick Jevic
                                      Senior Vice President

                                  IBJ WHITEHALL BUSINESS CREDIT
                                  CORPORATION

                                  By: /s/ John C. Williams
                                      ------------------------
                                      John C. Williams
                                      Vice President


<PAGE>

                                  HAMILTON BANK, N.A.

                                  By: /s/ Roberto R. Munoz
                                      ------------------------
                                      Roberto R. Munoz
                                      Vice President

                                  By: /s/ Adolfo Martinez
                                      -----------------------
                                      Adolfo Martinez
                                      Senior Vice President



<PAGE>

                          ACKNOWLEDGMENT OF GUARANTORS


            Each of the Guarantors  acknowledges  and agrees to the terms of the
foregoing Fourth Amendment to Amended and Restated  Revolving Credit  Agreement,
and  further  acknowledges  and agrees  that (i) all of the  obligations  of the
Company shall  continue to constitute  "Guaranteed  Obligations"  covered by the
Amended and Restated Guaranty  Agreement dated as of May 4, 1999 executed by the
undersigned,  and (ii) the Amended and Restated Guaranty  Agreement is and shall
remain in full  force and  effect  on and after the date  hereof,  and (iii) the
foregoing agreement shall in no way release,  discharge,  or otherwise limit the
obligations of such Guarantor under the Amended and Restated Guaranty Agreement.

            This  Acknowledgment  of  Guarantors  is made  and  delivered  as of
September 28, 2000.

                                               GUARANTORS:

                                               NUCO2 ACQUISITION CORP.,
                                               a Florida corporation



                                               By: /s/ Eric M. Wechsler
                                                   ------------------------
                                                   Name:  Eric M. Wechsler
                                                   Title:  Vice President

                                               [CORPORATE SEAL]


                                               KOCH COMPRESSED GASES, INC.,
                                               a New Jersey corporation



                                               By: /s/ Eric M. Wechsler
                                                   ------------------------
                                                   Name:  Eric M. Wechsler
                                                   Title:  Vice President

                                               [CORPORATE SEAL]