HCA: Hermit Crab Association

Hello everyone! I am getting back into crabbing after a very long extended break. I started my career with a 10G, upgraded to an exo-terra 18x18x18 then ended with a 29G since I was having trouble with humidity. I purchased glass for a lid and 2 second stories, one for a moss pit and one for a shell shop. Now that I am out of college, have my own classroom (public school teacher) and a garage full of tools I figured it was time to get back into it and go all out with what I have available! Unfortunately, I lost all my old photos of my old tanks but below is my 29G with the second stories.


This will be a long process, of which I have already started. As such, this will be broken into parts and will be updated as I progress. I am open to all feedback and hope everyone enjoys my build!


Part 1: The Topper
Since I have my spare 10G tank laying around (only ever being used in my classroom for demonstrations) I figured let's put that on top of my 29G. Easier said than done. The 29G is 12 3/16 in. wide and the 10G is 10 3/16 in. wide. To make up for the two inches I decided to make a wooden topper that would sit on top of the 29G and hold the 10G in place.

First, I removed one of the second levels so I can reach my arm into the tank and up into the topper if needed. I then made a small piece for proof of concept. The bottom groove will sit on the 29G while the 10G sits on the groove on the top edge.




The wood fit perfectly for both tanks so I moved on to making it for real. I took an 8 ft pine board, routed out the grooves, cut it into individual pieces, sanded the edges, notched the corners, glued it together and sealed it with linseed oil. I then decided to add a center bracket to the frame. It wasn't necessary for the topper but it will help hold my lid in place and I think it looks better! The wood topper itself sits very snug on the 29G and won't have to worry about it ever coming off or being pushed up by the crabs. The 10G is not as snug of a fit but still has a tight seal to the topper. I can wiggle it around and it doesn't budge. That was my first time working with a router so I am pleased with the results!







The remaining gap is about 8 in. wide. I know what you are thinking, "How are you going to access your tank?" My answers is simple, I am tall. Being 6'2" has its advantages sometimes. I can reached my arm into the tank, bend my elbow and can touch the far back corner of the topper. Even so, I won't really need to get up in the topper for anything other than to put a shell in the shell shop (that will come later). For a lid, I decided to use a glass lid and split it into 2 pieces. It will allow me to access the tank and not let out much of the humidity when doing small things like adding in breakfast. My old lid for the 29G was 2 solid pieces of glass so I repurposed them. With glass cutting around me being $10 a cut (not including cleaning up the edges) I decided to give it a shot myself with a $5 kit from Home Depot. After watching a bunch of YouTube videos and practicing on the second level I took out I was able to cut my lids. For the sharp edges I took some 220 grit sandpaper, wet it with the cutting oil from the kit and sanded away. The edges came out better then the glass I had cut for my original tank! Just be sure to wear a dust mask, eye protection and gloves if you plan on doing the same. I also tried my hand at drilling glass since it was $35 a hole at my local glass shop. Again, YouTube is a blessing. After a practice hole or two on the scrap second level glass, I tried it on the lids using a drill press, and it worked! These are the bits I used:https://www.homedepot.com/p/RYOBI-Speed ... /205193138 I added two knobs ($1 a piece) attached by 1 1/4" screws. These lids do not sit snug with the topper so I will have to design a system to hold them down. That is a problem for future me to figure out!





Part 2: The Layout
My tank will have a moss pit (the remaining glass second level), shell shop, bubble pools for fresh and salt, a foam background covered in silicon and coco fiber (this will have its own part later on) and a small fan for air circulation. I originally wanted to make a waterfall for the topper section of the build but scrapped that idea in favor of having more room to climb in and I won't have to worry about flooding or it breaking. Since no waterfall, bubble pools it is. With my previous tanks my bubble lines would come in from the top of the tank and dangle into the pools. Not this time! My original idea was to drill a large hole in the bottom of the tank (glass professionals would do that one) and have all of my lines go through a 3/4" PVC pipe and branch out to where they need to go. Well, the bottom of my tank is tempered glass and will shatter if drilled into. Besides that, I didn't want to run the risk of having the bottom shatter with the weight of the substrate even if it wasn't tempered so that idea was scrapped. I have experimented with drilling glass and it was time to try it again! I decided to drill two 1/4 in. holes 7 1/2 in. above the bottom of the tank (allows for 7 in. of substrate). Since this was done on the 29G I was unable to use my drill press and instead had to use my power drill. My setup had the glass being cooled with a water pump (was going to use on the waterfall) in a Home Depot bucket of water with my drill set at the highest speed and lowest torque. The drilling itself took about 2 min a hole but it worked! The tubes fit perfectly in the holes and will be at the correct height when the sub is added in.



Unfortunately, my drilling confidence went a little too far when I considered my fan. I read on a site that you should only drill into tanks that are 40G or higher since the glass is thicker. Anything below that can have a large risk of cracking. I needed a third hole that I originally was going to put in my 29G but figured nah, I can drill into that 10G no problem! The good news, the hole was drilled. The bad news, I cracked the side panel of the tank...
(The spray insulation is a preview for the next part!)


Oh well! Have to learn to move on. Instead of giving up and buying a new 10G, I grabbed a tube of clear silicone, put a small bead on the cracks and used an air cannon (attached to an air compressor) and blew the silicone into the cracks. I then put another thin layer on the cracks and a thick layer on the edges and surprise surprise, the tank is solid again! The silicon layer is invisible unless you really look for it and the crack will be barely noticeable when the background is done and the fan is in place. If I really hate it down the line I can always make another 10G topper and switch it out. That's the beauty of this design!


I am still in the process of completing Part 3: The Background so look out for that! There is a lot waiting involved allowing things to dry and air out but I might have it done next week. Or the week after. Who knows! I can only work on this project at night when I put the baby to bed or the weekends during nap time and I finally have some free time. Let me know if you have any questions, comments, concerns or ideas!

WOW, just WOW!

Sent from my SM-J337A using Tapatalk

One week later? Two weeks? How about 3 years later! My tank build was put on hold after the initial post as the school year was ending and didn't want to finish up and then leave it for months before the start of the new year. Then, I decided to postpone my build until I was able to adopt from someone local. That only took 3 years, but I adopted 1 crab last month which set my tank building back into motion!

Part 3: The Background
I decided to make a background after reading through almost all of the posts here and seeing how good they looked. To do this, I used spray foam insulation, silicon, wood, eco earth and moss. I apologize but some of my photos are missing since I misplace my SD card when I got a new phone.

First, with my tanks on their sides, I put a layer of black silicon in the areas that I will add a background to. This isn't necessary to have the foam stick to the tank. It is purely cosmetic since I didn't want to constantly look at the yellow spray foam from the side. Once dried, I set a few pieces of wood in angles that I wanted and then sprayed away. The wood held in place perfectly.


Next, I added the texture. I mixed eco earth and some exo terra forest moss and let it dry out completely. Then, I smeared sections of the insulation background with clear silicone using my hand and a glove, then dumped the eco earth mixture on top and smooshed it down. This part was messy and time consuming. I had to let each part dry, clear away the extra mixture, and patch up spots that I missed. It took a few days of adding the eco earth then an additional week to make sure all of the fumes were gone, but I really enjoyed the results!


Here it is after adding in the sub and my lights:


Part 4: Water
My original plan for two bubble pools for fresh and salt water. After reading for months and months, I decided to try to cycle a tank of fresh water. Using this forum and other sources, I was able to cycle a 1-gallon pool of fresh water using an air driven corner filter filled with filter fiber and some shells for weight. It only took 4 months, but it didn't matter much as I was waiting for an adoption opportunity. That pool ran cycled for over a year in my classroom. My students were very confused seeing an "empty" tank running constantly. The only downside was that the 1-gallon tank was too big for this build, so I transferred the filter and water to a smaller glass tank I found at my school. I then constructed a pad and ramp system using plastic egg crate, zip ties, and craft mesh to allow crabs a safe place to get water and relax. I know purple pinchers don't usually go swimming, but I won't let my dreams die out yet! Even if they never swim, the pool is a great humidity booster. Since one air line is tied to the filter, I used a splitter to have a bubble in both the large pool and saltwater pool.




More to come soon! Look forward to finished pictures of my water pools, my battle with temperature and humidity, addition of a fan, and final pictures of the build.

Oh right on! I love updates like this!

Look absolutely amazing!! Great job! I can't wait to see the finished product! Where did you get the white grate for hermies to climbing on?