Membership Information


Anyone interested in keeping ornamental fish, plants, and other aquatic animals is welcome at our General Meetings to hear knowledgeable speakers at our monthly general meetings. While visitors are welcome, to participate in our auctions or other events and activities membership is a requirement.  The good news is Membership is free, just fill out the application below.  There are benefits to becoming a member, some of which are mentioned below. We are confident you will recognize the value in this. Apply Below

No annual membership fee till further notice


A few benefits of becoming a member:​

  • Membership is a requirement for participation in any CAS sponsored event or activity. 

  • 80/20 split on sales at the auctions.

  • Great information and help on all aspects of keeping and breeding ornamental tropical fish from local hobbyists who genuinely share an interest in your success as an aquarist.

  • Being notified of any and all special events, field trips, and activities.

  • Being a part of helping promote and grow the club and the aquarium hobby in general.

  • Contributing to CAS's ability to share knowledge and provide speakers and meetings to the public.

Competitions and Awards



Bowl Shows are held at each General Meeting and have two predetermined classes and one open class. The December Bowl Show is the Championship show. All First Place winners from the previous 11 monthly shows are eligible to be a Champion!

For more information on bowl shows, Click Here



CAS holds two growth contests each year:

The Plant Growth contest starts in April and ends in October.

The Fish Growth contest starts in September and ends in March.


See our CAS Handbook, p.34 for details.  Use contact page for questions or submissions. Click Here for the BAP Spawning Report Form



Members are encouraged to accrue points throughout the year. Points are accrued through a variety of different aspects associated with the club. The member with the highest number of points at the end of the year is awarded the Aquarist of the Year Award.


We invite you to join us on Facebook and Instagram.  We have contests, sharings, and the occasional give away.  Please use these platforms to share and learn the hobby.  

Business Sponsors

Click on Logo to go to their site

Aquarium Hobbyist Magazine is the hobby’s favorite freshwater aquarium magazines. Free in over 1,000 local fish stores in the U.S. and available for free online to the rest of the world, these magazines aim to inspire people to learn about and enjoy nature by creating beautiful aquariums. Pick up a hard copy or visit our website to read the digital issue. You can expect the latest husbandry techniques, new equipment and product information, animal care guides, and examples of some of the world’s most beautiful displays. Check out Reef Hobbyiest Magazine too! 

Membership Application
Membership Type
Par Meter Program

The Apogee MQ-510 par meter is a precise instrument used to measure PAR in the aquarium and we offer one to our members to use at our General meetings.  It can also be checked out for one month at the meeting and returned at the next meeting.  A deposit of $550 (full cost of the meter) on a credit card is required.  See someone at the check in desk for more information.  

CAS Handbook 2020

Contains our Constitution, By-Laws and all program details.  Required reading for all members.

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Support your Local
Fish Store
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Use the following list to find a LFS (local fish store) near you and give them your support.  Colorado is blessed with a great number of excellent fish stores, esp. along the front range. 

Colorado Fish Stores that we know of:


If you find a listing in error or if you know of an omission, please use the contact page to let us know about it. 

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