POTO Floating Reef - How We Did It

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Pieces of the Ocean

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During our Live Sale, we were asked how we made the rock work in our floating reef display. The idea was inspired by something a German reefer did on his nano that I came across which I can't find the link to now. But we made some adjustment to the idea to fit our needs, specifically for a bigger tank than a nano which meant a heavier structure. The tank we have is a 93g cube measuring 30x30x24. We also wanted the rock to hang off the ledge a bit more. Here's the tank.




The structure sits on a 1/4" thick extruded acrylic sheet bent to 90 degrees. I find that this is the ideal thickness as it's not too thick, so that it allows the structure to bend to the weight of the rock a bit, but not too thin that it couldn't hold the weight. We also chose extruded instead of cast acrylic because it's cheaper and more malleable under heat. Then we used a heat gun to heat bend the acrylic sheet to 90 degrees (over bend it a little to account for when the weight bears down that it will bend a little). I used 2 scrap pieces of plywood to clamp to the acrylic sheet for a uniform bend.


The acrylic softens after about 5 minutes under the heat gun at 320 degrees. Here's a cheap one I found on Amazon.


The acrylic hardens in about 1 minute so you have ample time to make your shape.


We ended up making two of these, on on top and bottom for extra strength.


You can see the 2 acrylic sheets in this photo. We also bent the top portion for a little ledge to create depth in the eventual rock work. Holes were drilled to allow water movement between top and bottom of the structure.


And here's the most important part of the process. We cleaned all the surfaces with alcohol, and used a specific type of silicone made for plastic. We first used one specifically made for aquarium and it did not hold the weight and the structure peeled away under the weight like a fresh new credit card. So I did more research and found this in the window section of HomeDepot, not the paint section where they usually stock silicone. So if you are going to attempt this, make sure you are using this silicone. It is reef-safe as long as you cure it long enough. We cured for over a week before touching it. And longer is always better. Silicone on custom aquariums take a month to cure.


Small rubble rocks were then glued to the edges of the acrylic using epoxy. That way the actual larger rock we place on there can catch their edges and hang outward more, creating more of a floating effect.


The tip of the bottom rock hooks off the rubble rock and hanging just 2" off the sand bed. This would not be possible without the rubble rock around the edges of the platform.

And that's it. We plan on removing some rocks as the corals start to grow and allow them to fill in the space instead of the rocks. Thank you for reading and please let us know if you have any question.
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Kendrick Brown

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Love this aquascape! Guess we had the same idea from coral_fish_zoa. Heres a link to my that i did in a fairly similar way if youre interested. Hope more people pit in the work like yours because these are so enjoyable to see how others did theirs! How does that nem do? Does it stay in place? I was thinking about it but didnt want it to just take over my entire rock if it climbs the glass.https://www.reef2reef.com/threads/floating-shelf-aquarscape.763804/

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