Build an Artificial Reef





Introduction: Build an Artificial Reef

About: I hang out in Costa Rica and build fun sustainable, eco, survival related projects.....My main goal is to be able to feed the family totally off the system. I'm a big fan of Aquaponics

Some reefs are erroneously constructed from car tires (a bad idea due to the toxicity of rubber disintegrating in salt water), and some are built using broken-down cars, old boats and scrap metal.  Our goal was to ensure that fish and other marine animals, such as crabs, octopus, and eels, looking for a place to live and reproduce had the best environment available.  The reef project chose cinder block because the block was much easier to handle than cars and other heavy industrial items and the Calcium content of concrete bolsters the growth of various plant and invertebrate life forms.  Also, logistically it made more sense because block is readily available.  The fish habitats are formed into an “igloo” and “caterpillar” shapes  which offer the best environment to live, breed and find protection. 

Step 1: Choose Location

The very first step is to choose a low current location that is conducive to undersea life, reproduction and feeding.

In 1985, a 60-foot tuna-fishing vessel of Mexican origin was anchored close to the beach in Playa Hermosa. A fire broke out aboard causing considerable damage and the boat sank. In 2002, fishermen living in Playa Hermosa knew the location of boat and helped discover the wreck and the remains of the fishing vessel. The wreck has a N-S direction. To the south is a drum with nets and ropes completely covered with vegetation and corals, at the center is the engine and various mechanical parts of the arms. At the other end, the north, one can see a metal cube of about 100 cubic feet that is most likely a fuel tank. The wreck lies about 400 meters west from the beach, facing the parking lot of the first entrance to Playa Hermosa. It sits at a depth roughly 20 to 30 feet depending on the tide. 12 fish habitats consisting of the igloo block structure are located around the wreck..

While the CondoFish project in Playa Hermosa Costa Rica obtained full government approval for the project, this may or may not be relevant in other international locations. Costa Rica is a very ecologically conscious country and anything regarding natural resources or wildlife requires approval and constant surveillance.

Step 2: Test Reef Design Outside of Water

While you may have a good idea of what your design will be.  We highly suggest testing your design outside of the water.  This will save valuable building time underwater. 

The following steps will show the design that the Playa Hermosa Artificial Reef Project used.  It seems to be good design to start with.  After a 3 month period, an explosion of aquatic life has occured in the in and around our "fish condos".

Step 3: Move Materials to Site

Move your materials to your building site.  We chose a clean patch of ocean floor and dropped the cinder blocks one by one.  Then we built the Reef structures by moving the blocks from the pile to the building site. 

Step 4: Build Your Base

Build your base on level sea floor.  Anchoring should not be needed if the location chosen is calm enough.

Step 5: Add Levels 2, 3, and 4

Build the sides up to the 4rd level.

Step 6: Add the 5th Level and the Center Support

Add the 5th level and the center support.  The 2nd image is a cutaway shot to show a better view of the center support.

Step 7: Monitor, Maintain and Protect

Now, monitor maintain and protect.  We make weekly visits to the site and constantly think of way to make things better.  Pending approval, we'll be building more structures and requiring more and more support.

Step 8: Progress Pictures After 1 Year

It's been nearly a year since we dropped the first blocks in the water.  What was once a bare sand bottom, is now teaming with life.  The blocks are covered with calcium based creature, soft corals, crabs, fish eggs and school of fish frequent the area.  Add to the that the life in the Benthic zone under and around the structures is doing very well.  



    • Water Contest

      Water Contest
    • Game Life Contest

      Game Life Contest
    • Creative Misuse Contest

      Creative Misuse Contest

    93 Discussions

    This is awesome, I am a certified scuba diver (PADI) and would love to do this in a local river nearby.

    1 reply

    Great job! Thank you for helping the environment.

    oh the beautiful fish on your site! they must be so happy! awesome job :) say, what do you think about putting something like this in an artificial pond in New England? just wondering

    Nice job guys, lets just say theres some people who care about the planet. To says its that easy and cheap to make a home for many, absolutely brilliant, well done :) :)

    This is excellent! I'd love to follow the time course in photos as fish colonize your artificial reef. Will they be posted on your site?

    1 reply

    Yes, the adrian stacey gallery is right after we got the fish condos built. The gallery is the most recent we have some new pics and a video that should be going up in the next day or so. I'll continue to add photos for 2010, then make one for 2011.

    Well, anytime you want to come dive it, you're welcome. And donations are accepted via our website via a Paypal link on the sidebar of our site. Thanks for your support! And come check out the site and look around. Thad


    What are the dimensions of the reef?


    1 year ago

    This is amazing, can I build it higher like high enough to see above the sea level or is that impossible :D

    Beautiful job! I'd like to try this off Ocean City, MD.


    2 years ago

    Very nice idea ! Good luck to everyone

    This is so cool, please put some more pics of this as it grows.

    Are you extracting those tiger fish? I saw a picture that looks like you have one in there.

    Have you got any update pics. Would love to see how the reef is going.

    have u thought of doing a under water type of camera tethered to a small buoy thats set up 4 solar charging an wifi?