In its 20 years my acrylic tank has housed a variety of fresh and salt water fish, including seahorses, and for the last year it has been home to my two hermit crabs, Snake Pliskin and Handi-Crab. Knowing how much hermit crabs like to climb, the vertical format allows them a nice sea fan and cholla stick with several inches to spare at the top to avoid any escapes.
This tank has seen better days. The acrylic has gotten scratched up and foggy in places, as acrylic is prone to do. You could see the fine wispy scratches where I had wiped the insides with a not-so-great dollar store sponge, and cloudiness around the gravel line where rocks had also caused abrasion. Top it all off with the crabs shoving their food around and smearing calcium supplement on the walls, and this place needed a big time spring cleaning makeover!
In this Ible, I'll show you the process I used to re-surface the acrylic and freshen all the furnishings in ways that are safe for tank inhabitants. I also decided to create a faux mushroom platform to utilize more of the tank's vertical space, giving the crabs a second floor destination. We'll walk through the building of that platform and discuss alternative designs for different types of animals.
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Step 1: Prepare to Clean
Remove the Residents. I used a clean fishbowl as a Crab holding area while I did my work. The curved sides ensure that nobody will be able to climb out while I'm not looking. I transferred their moist sponge over with them and gave them their favorite treat foods as a consolation for the inconvenience. If you have cats, dogs, or small children, put your holding container somewhere high up and secure, like on top of the fridge.
Remove Tank Decor. I took all the "furniture" out and placed it in a clean plastic bowl. This keeps everything together in one location and prevents your tank decor from getting contaminated with carpet lint, pet hair, unwanted household chemical residues, etc.
Scoop out the Substrate. My substrate was a mix of fish tank gravel and Jungle Bed, but the crabs have burrowed and upturned it so much over time that it had become just dirty gravel. Time for some fresh bedding!
Use a cup to scoop out the substrate and place it in another clean plastic container or bucket. The container you use should be one that has NEVER been used with cleaning chemicals (bleach, 409, soaps, etc.) You don't want any chemical residues getting on items that will be used in a terrarium. aquarium.
Scooping with a cup may take a few minutes, but it's the smart way to empty the tank. Pouring out the gravel can be awkward with a large tank, and may result in even more scratches to the acrylic.
Step 2: Rinse the Substrate
I wanted to separate the gravel from the old funky Jungle Bed.
To do this, you simply fill the bowl with water and mix with your hand. The lighter, fibrous debris will float to the top while the gravel remains on the bottom.
DO NOT USE ANY SOAPS! Water and agitation is all you need. Do not use soaps, not even "natural" or organic brands, to clean gravel for an animal's tank.
I poured the excess debris and dirty water into my garden. The uneaten foods and critter waste can be put to work as fertilizers, and the bits of Jungle bed will decay naturally. I don't know what all was in that waste water, but I will say that some long-dormant seeds I had in that planter magically sprang to life after receiving this run-off!
Rinse and Repeat 3-4 times, or until your gravel returns relatively clear water.
Step 3: Wipe Out
You need to prepare your acrylic for the re-surfacing polish properly in order to get good results.
Wipe down the tank walls with a clean, slightly damp cotton dish towel. These are what I use to clean glass when framing artwork because they're very lint free.
Never use paper towels on Acrylic --they can scratch! I'm sure a few of the blemishes I have to correct now are due to a moment of laziness where I thought "Hmm...I wonder if it really WILL scratch...*wipe wipe*..Yep. It sure did.
After major debris crumbs are cleared, do a second wipe down with rubbing alcohol. This was a step recommended by a guy at the aquarium shop, to get all the finer dust and hairs off the surface before scrubbing.
Don't forget to wipe down the tricky places, like the underside of the acrylic top.
Step 4: Re-Surfacing
I purchased this bottle of Novus "Step 2 Fine Scratch Remover" from my local aquarium store. They also make "Step 3" for deep scratches that you would use as the pre-scrub to this bottle, but I felt most of my tank damage was hair-line stuff probably categorized as "fine".
I would liken this stuff to auto scratch remover or the kits you use to re-surface headlights, as the process is much the same. It has a very, very fine grit to it and when rubbed in a circular motion will re-surface the area. It works by taking the level of the surrounding acrylic down to the same level as your scratches, thus creating a smooth plane again.
Squirt a quarter sized dollop onto a microfiber towel (I used the type you might use for auto polishing).
Apply to the acrylic and rub in a circular motion. Apply firm pressure.Remember, you're trying to scrub the surface down to one even level. This will take a bit of time and elbow grease. Depending on your tank size, you may benefit from asking a friend to hold the tank while you scrub, to allow you to focus on your pressure.
Rub each section until the greasy look of the product has vanished. The acrylic will remain a bit cloudy and you may not be able to access the results until after the next wipe down.
I only resurfaced the 3 clear acrylic panels in the front and left the black panels alone. As far as I could tell the black panels were in much better shape, probably due to less needed scrubbing over the years.
I found it helpful to work in thirds down each facet of the tank. This made it easier to keep track of where I had already been and make sure each section, inside and out, had been addressed.
Make sure you work down past the gravel line and into the corners as best you can. Try making circles with two fingers instead of your whole hand for tight spaces.
Step 5: Final Clean Up
If you've put enough time and pressure into your Novus application, your fine scratches should be gone or much improved.
To eliminate the product residue, I took the tank outside for a good hosing down, inside and out.Use a gentle "shower" setting, not a high pressure blast. Forceful water jets could knock over the tank.
*When working with water, be mindful of any electrical components attached to your tank. I have a ZooMed heat pad attached to the side for the winter months and those are not removable once applied. Avoid excess moisture here and wait several hours to ensure a full dry before plugging the device into the wall again.
Dry with a cotton dish cloth. You should start to see the results of your work, though a little streaky/greasiness from the product may still be present.
Do a 2nd Rubbing Alcohol pass with a clean section of cotton dishcloth. This should leave you with ultimate sparkling clean! The surface of my acrylic was much improved. The tank was clearer and looked years newer than before. I tried getting before and after pics of the scratches but they were so fine to begin with it was hard to perceive in photos. Take my word for it --worth the time and $14 for Novus polish!
Allow 10 minutes or so for all product odors to fully dissipate before re-introducing your tank goodies. If you're doing this for an aquarium, you may wish to wait a full 24hrs before re-filling with water (store guy's suggestion).
Step 6: Fresh Substrate
Using your cup from before, you can re-introduce your clean gravel to the tank bed. I distributed more gravel in the back to create a small hill. My crabs seem to enjoy burrowing in gravel, so I'm providing a little excess for them to shift around.
I wanted approx. 50% of my flooring to be Jungle Bed, a preferred substrate for hermit crabs. For some reason my crabs don't seem crazy about sleeping in it, but it does a great job of holding moisture and thus creating humidity in the tank. Again, the crabs are going to kick things around and get the consistency they want anyway, but this is a nice clean way to start.
Step 7: Decor
A spring cleaning is a good time to re-invigorate or enrich your pets tank decorations. Think about what you've observed them using or preferring the most, and how you can maximize their use of the space.
Natural corals are a great option for hermit crabs. They make great playground equipment and also host calcium and other minerals that the crabs can pick off and ingest. I'm fortunate to have a wide variety of corals left over from my mom's old aquarium business.
If you've purchased a new tank decoration from the pet store, always give it a quick rinse in clean water to rinse away any shelf dust, hand lotion from a clerk, or other unseen debris. I can't say this enough --NEVER USE SOAPS! My mom would have clients come crying when their fish tank turned all sudsy and killed all their fish, ...because they thought you could use dish soap to clean algae off of tank decorations. Even if you think you've rinsed it all off, you haven't. Just. Don't.
Consider what's best for the animal, not just entertaining for you. I LOVE this plastic tank decoration of Bert from Sesame Street snorkeling with an eel. It's funny and colorful, and has been a great piece in this tank when I've used it for fish. However amusing it may be, I noticed that the crabs were nipping off part of the flipper. I have no way of knowing whether they were eating the plastic, but funny tank decor isn't worth risking their health. I've rotated Bert out in favor of natural pieces that can't hurt the crabs.
I like using natural shells as food and calcium dishes. It looks nice, and it's one less plastic thing to worry about them nibbling. I suggest placing your calcium dish toward the center of the tank. If you put it next to the glass/ acrylic, they will inevitably smear it everywhere and cloud up your view again! I DO use a plastic, faux rock water dish. It is nonporous and easy to clean, and provides a level surface area to keep the water in the bowl and absorbing into their sponge.
Sea Fans and Cholla pieces are excellent for these skillful climbers. Those major pieces, combined with coral chunks and interesting shell fragments, make up a diverse playground for hermit crabs. The last two photos show my preferred layout. The crabs have already overturned and re-arranged some things to suit themselves, and that's ok.
Step 8: Homecoming!
Your residents can finally check out of their hotel and go back home! Snake Pliskin did me the favor of grabbing the sponge (1st photo).
Here are some photos of them exploring the freshly clean space, just for fun.
Step 9: Improvements: Mushroom Platform
I started to wonder whether I could make better use of the vertical space leftover in my tank. Sure, I gave them tall things to climb, but was that a cruel joke if there was nothing to climb TO? Was that like someone building me a house with stairs that go nowhere?
I decided to build a faux mushroom platform that the crabs could land on after climbing up. It gives them a place to settle, and I figured I can put treats up there as an incentive to use their climbing furniture. The look is inspired by those awesome glowing mushrooms the characters hop around on in the movie Fern Gully, if you're old enough for member that.
You Will Need:
Scissors or craft blade
Crayola Model Magic
Rubber Tipped Scultping Tools or toothpick/ popsicle stick
Craft Acrylic (chosen colors)
Spray Clear Coat in matte or satin finish
Small Suction Cups or powerful magnets
Step 10: Sizing the Platform
Measure the side of your terrarium.
Since I have a hexagon tank, the width of my platform must be less than the width of each acrylic panel.
Mark out that width on your scrap cardboard.
Draw an irregular mushroom top shape within those bounds. For inspiration, google "amazon rainforest mushrooms".
Cut out the shape. Use scissors or a craft blade. The cardboard is just a skeleton for your final form, so your cuts don't have to be super elegant and precise.
Step 11: Mushroom Tiers
To create the growth layers of your mushroom, we'll retrace and size down our original shape twice.
Trace the original, hanging the flat edge off your cardboard.This will ensure your next layer is a little shorter than the first.
Look at your traced outline. Now loosely mimic the line 1/4 -1/2 inch inside the original. Your 2nd layer is now narrower than the first. Cut out the second shape.
Repeat by tracing the second layer. Make a shorter and smaller one based on that. Cut out this third shape.The smallest of the 3 is your third (bottom) layer.
STEM-- To make the stem of the mushroom, sketch a vertical shape based on the width of your platform. It can be short and stumpy or long and narrow, depending on your natural inspiration. Think organic, and don't worry much about symmetry.
Step 12: Safety Lip
I decided it might be a good idea to have a bit of a ledge on the platform. This will help hold treats on top and maybe (maybe) prevent the crabs from diving off the side.
Trace the original (largest) platform shape.
Mimic the traced line about 3/4 inch inward.
Cut out this thin strip.
Apply white glue to the ledge strip and apply it to the edge of your platform.
Clamp in place to dry.
Step 13: Assembly
You'll be assembling the mushroom growth rings in layers to get your overall cardboard skeleton.
Apply glue to the top of your smallest platform layer.
Press into place onthe bottom of the medium layer. Clamp to dry.
Apply glue to the top of your medium layer.
Press onto the bottom of the top layer. Clamp to dry.
You'll see them stacked logically and your mushroom form emerges.
When the platform chunk is dry, you can attach the stem.
Apply glue to the upper third of the stem.
Press onto the flat back of the mushroom chunk.
To ensure a perpendicular bond, you may wish to brace the stem against a flat object like a book (or a Pigs in Space lunchbox).
Step 14: Choose Attachment Method
My hope was to use magnets to support the mushroom, which would give this a totally natural, seamless look. However, after testing out several types of magnets we had at home, I found that none were strong enough to support the weight of our larger crab. The platform would just slide down the side of the tank like a one way elevator.
To get a secure, stationary bond to the tank wall, I decided to go with small suction cups. We'll see the tops peeking out in the end, but that's a small price to pay for a functional solution.
To create recesses for the suction cup heads, I started by tracing then onto the back of the stem. I placed one near each corner, for even distribution of support.
Cut out the holes using an x-acto, first tracing the outline of the hole and then using the tip to scoop out the cardboard piece.
The head fits snugly into the recess. We'll secure these with adhesive later in the process.
Step 15: Sculpting
I decided to use Crayola Model Magic to flesh out my cardboard mushroom skeleton. I chose it for the fact it is lightweight, and for the soft spongey texture that reminded me of a real mushroom. Smooth-On Free Form air clay was another good option I considered, but I ultimately decided against because it is a 2- part mix.
Start at the base of the stem. Apply a chunk of MM large enough to smooth out and cover your cardboard footprint.
Slope the MM up gradually, so that the stem meets the underside of the platform in an organic joint.
Using smaller pinches of MM, begin to cover the underside of your platform. Use your thumb to press and smooth as you go, keeping your application thin and true to all those nice ridges on your frame.
Continue until the underside is covered. Use your thumb to smooth out obvious seams of adjoining MM sections.
When the underside is complete, wrap MM up over the edge and begin to cover the top.
Keep your MM application on the top very thin, so as not to lose the definition of your safety lip.
Use small pinches of MM to cover edges and plump up the corners, making them flush with the back of the cardboard stem piece. DO NOT cover the back of the stem where your suction cup holes are. We want to keep this surface nice and flat, and adding bulk can only jeopardize that.
Step 16: Texture
This part was the most fun for me.
Use a rubber tipped sculpting tool to definite organic looking lines and ridges in your mushroom. if you don't have sculpting tools, toothpicks and popsicle sticks will do --they'll just make harsher lines.
I used the round tip to define the ridges on the underside and the flat tip to make the safety lip stand out more. The beveled edge of the flat tip was great for drawing ridges in the lip.
Vary your line work. Have some that don't wrap all the way around, and mix up the distance between neighboring lines. Press harder for deeper grooves and just barely brush for something subtle. *Note: MM is a little spongey and bounces back a little when you draw lines in it.
Texturize the top of the platform. This not only contributes to the natural look of the piece, it also provides ridges and grooves that will help the hermit crabs maintain a good foothold.
*Note on Dry Time: The Model Magic package specifies that the form will be dry to the touch in 24hrs, and fully dry after 72. Since our application was thin, I found it to be thoroughly dry and after 2 days.
Step 17: Painting
I used craft acrylics so that I could mix a custom color and give some detailing to my mushroom. If you just want to do a one color application, you could substitute a coat of spray paint for this step.
Look to nature for your mushroom color inspiration. I mixed a natural yellow/ khaki color to mimic the rainforest tree mushrooms I had in mind from the start.
Put down newspaper to protect your work surface.I used a scrap of my leftover cardboard as a paint palette for mixing my custom colors.
The second photo shows the ratio of yellow/white/beige I used to create my color. Yellow paints are often semi-transparent and require mixing with a bit of white to get opaque coverage, so keep that in mind if you choose to use yellow for your project.
Apply your base color with a sponge-type brush, almost dry brushing the color across the surface. This technique will prevent paint from pooling in all those nice lines you carved.
Add another squirt of white to your base color to create a highlight color. Dab this color on top of your platform where the mushroom would naturally be lightest.
Add a deep brown (I used Burnt Umber) to your base color to create a shadow color.
Use a paintbrush with a fine tip to apply shadow color.Accentuate the grooves along the edge, the rim of the safety ledge, and the lines on the platform and stem. Don't worry about being super precise. Varied line width and dappled color will contribute to the organic look of the piece.
Optional Black Light Reactive Layer! For the full Fern Gully effect, I wanted my mushroom to be able to glow.
Dilute a dab of backlight reactive acrylic with a transparent, matte finish. Apply with a brush to give a wash of florescent color to the platform.
I opted to dab back the excess liquid paint with a napkin before letting it dry. This gave my glowing areas a more natural, mottled look, rather than being a flat, artificial glow toy appearance.
When your acrylic is dry, apply a coat of spray of protective clear coat in a matte or satin finish. Something meant for indoor/outdoor that cites moisture proofing will be best for terrariums with humidity. Without a protective clear coat, your patin will peel and the cardboard may fall apart. Make sure to the hit the flat cardboard back, since that is still exposed.
Do NOT use a gloss clear coat. It will take away from the natural look of the piece and potentially make the platform more slippery for your critters.
*SAFETY NOTE:Execute your spray-on application in a well ventilated area, preferably outdoors. Use in a spray booth, or put newspaper under your work to protect the surface underneath.
Step 18: Suction Cups
The final step is attaching the suction cups (or magnets, if you have ones that are proven powerful enough to hold the weight of your pet).
I settled on a 2 part epoxy from Harbor Freight as my adhesive. My hope is that it will be the strongest and long lasting in a humid environment.
Mix equal parts of epoxy on a scrap surface.
Apply to the inside of your suction cup recesses using a toothpick. Dab in just enough to fill the holes to their brims.
Insert the heads of the suction cups into the recesses, which should still be a perfect fit. Hold here a moment to let the adhesive gel a bit.
Ultimately you'll want to leave your mushroom to dry on a flat surface, while resting on the suction cups. This is a good way to guarantee that the cups won't tilt while drying. I let the epoxy cure overnight before installing the platform.
Step 19: DONE!
The acrylic tank got its much needed makeover and the crabs got an "upstairs" room to enrich their playtime and foraging. I've been pleased with the performance of the suction cups and they actually aren't too intrusive on the illusion. The crabs figured out the up and down pretty quickly.
For slightly larger pets, like geckos, you may want to test out some high powered earth magnets as your attachment method. I have a similar faux rock shelf in my leopard gecko tank that uses quarter sized, super strong magnets to adhere it to the glass (like, super strong magnets that practically leap out of your hand). These will hold a 45 gram gecko with no trouble. Experiment and find out what's right for you.