HCA: Hermit Crab Association

Will be building up a 50 gallon tank this weekend using acrylic to make two mini tanks and two platforms. Here are the blue prints.


I currently have 3 crabs. And was wondering how many more I could add when I upgrade.
There are 403 square inches of sub, 192 square inches of water, and 235 square inches for the second floor. I was thinking in the ball park of 6-12 crabs total. Let me know what you think.
Stay tuned for the build!

Awesome! Be sure to keep us updated. As for the crabs, it depends on what size they are. But be sure to check the links I added out-- hopefully they'll help! I know the HCA and JediMasterThrash really helped me out with these!
https://www.hermitcrabassociation.com/p ... 26&t=92541
https://www.hermitcrabassociation.com/p ... ll#p836451

Drew out the components in my CNC program today. Will be cutting the pieces tomorrow


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That's actually super neat! I'm not very good with electronics and would never have the skill to make a tank myself I think the design looks great nonetheless!

I’m actually just using a standard 50 gal and making fixtures to go inside of it. Originally I was going to build the water tanks with 1 sheet directly siliconed into the tank but I decided to make everything removable.
My only concern is the ramps : if they take up too much width of the tanks (they take up about half the width of the water tanks) and that the angle is too steep for the crazies to climb down.


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The first structure is done. This will be the fresh water tank.


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Oops! But I still think the construction of the water "tanks" (bowls isn't the right word to me, since they're way bigger ), and the fact you got to "design" or model it on a computer somehow is cool! And about your concern with the ramp- in my opinion, as long as they're able to grasp it I think they should be okay (The slits in the glass are a good place for them to grip with their claws!). But I'm not so sure. My bowls are pretty small so I've never had to really think about that, sorry. Are you concerned they won't be able to get out (climb), or that they won't be able to submerge? I'll try to help if I can, but like I said, I've never really thought so much about it.

Here are all of the assemblies, just waiting to dry. The large salt water tank is too large to put in the tank width wise as originally planned.



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I need a little help. I am trying to arrange the things I built in the tank. Two of my pieces are supposed to fit in sideways and they would but the lip won’t let me put them in that way. Is there and way I could alter the lip or remove this cross bar to make them fit?

The red outlines are supposed to be turned 90 degrees.


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Here’s photos of the large salt water tank with Lysol for perspective. I’m just wondering if the ramp is too wide that the crabs might not be able to get all the way in.




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quinnmquinn wrote: ↑

Wed Apr 15, 2020 7:10 pm

Here’s photos of the large salt water tank with Lysol for perspective. I’m just wondering if the ramp is too wide that the crabs might not be able to get all the way in.




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Hm-- how big are the crabs?

Hm-- how big are the crabs?

I’d say the largest is a little over 4 inches and the smallest a little under 2 inches. There are 3 of them.


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Hi what do you think the cost of making your water encloses is is it hard to cut a d bond them together
I only ask because I have a idea that I've been wanting to do for awhile for a side by side salt and fresh but every acrylic fab place I've contacted hasn't contacted me back so maybe it's to small of a project

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SixBitSamurai wrote:Hi what do you think the cost of making your water encloses is is it hard to cut a d bond them together
I only ask because I have a idea that I've been wanting to do for awhile for a side by side salt and fresh but every acrylic fab place I've contacted hasn't contacted me back so maybe it's to small of a project

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The only real cost would be a sheet of acrylic and silicone. A sheet of acrylic for this size project would probably be $20-$100, depending on size you need. Here’s a website to gauge: https://www.eplastics.com/plexiglass/ac ... ear?page=2 . I’m thankful my dad had some scrape laying around his shop.
As far as assembling it I had a pretty easy time because each tank is only one piece of plastic. I used something to heat bend the corners and then I only had 4 corners to glue, and since it was already bent it shape it was easy to hold it’s form when being glued. Here’s a pic that hopefully describes what I mean by 1 piece:

The con to this method is when I heat bent it the corners grew because of the heat now one piece doesn’t fit the way I originally planned.
They also aren’t all perfect 90 degree angles.

I’m guessing a heat bender might not be accessible, in that case you’d have to cut the pieces individually and silicone them, which would probably take a lot of clamps and/or supports and be more drawn out in time. It can be done though, I’d just suggest doing 1 corner at a time and letting it dry so it doesn’t all lose shape while drying.
The con to this would be there would be a lot more areas depending on silicone to hold it together. And might be harder to make leak proof.
I am still working on getting mine not to leak with only 4 seems.
Hope this helps!

What are the dimensions of the water tank? I honestly think they should be okay, as long as when they get to the bottom they will be fully submerged. The bridge should be able to help them climb out, all though I'm not sure if they would be able to turn around. Trying my best to help!