Build Magnetic Reptile Terrarium Ledges and Hides
Matt Pennebaker builds magnetic cork bark ledges, feeding stations, and hides for reptile and amphibian terrariums. His shop, Holdfast Habitats, has a 4.9-star rating across more than 450 Etsy orders, and every piece he ships is held in place with totalElement neodymium magnets.
- 4.9★Etsy Shop Rating
- 450+Orders Shipped
- 5.4 lbPull Force per Magnet
- 0Drill Holes or Suction Cups
A better way to mount decor in a reptile terrarium
Anyone who keeps crested geckos, gargoyle geckos, leachianus, or tree frogs knows the problem. Arboreal animals want to climb and perch high in the enclosure, but getting a ledge or hide to stay put on smooth glass is harder than it sounds. Suction cups let go in high humidity. Silicone and adhesives are permanent and make deep cleaning a chore. Drilling isn't an option for most tanks.
Holdfast Habitats solves this with magnets. Each accessory is a two-part mount: one bracket holds the cork bark inside the enclosure, and a matching bracket sits on the outside of the glass. Neodymium disc magnets in both halves pull them together through the glass, clamping the piece in place. There's nothing to stick or drill, and when it's time to clean or rearrange the enclosure, the ledge comes right off and goes back on wherever you want it.
Hand-fit cork bark, built to hold a full-grown gecko
The magnetic bracket is intentionally simple. What makes each Holdfast Habitats piece stand out is the cork. Natural cork bark is never the same shape twice, so Matt hand-fits each piece to its mount. The result is a lineup of ledges, feeding stations with built-in cup holders, and hides with a "viewing window" that lets keepers see their animals without disturbing them. Mounts come in several colors so they blend into a planted vivarium or pop against the background.
These aren't small pieces, either. The shelves are sized for large arboreal geckos, so the magnets do real work, holding the weight of the cork plus an adult animal jumping on and off it every night.
“Every product we make uses totalElement magnets. They're the only magnets we trust for this application.”
Matt Pennebaker, Founder, Holdfast Habitats
The magnet behind every Holdfast Habitats mount
Matt builds his mounts around our 7/16 x 1/8 inch N42 neodymium disc magnets, rated at 5.4 lbs of pull force each. That combination is the whole story: the disc is wide enough to exert real holding power against the glass, slim enough to sit flush inside a bracket, and consistent enough from batch to batch that every mount he ships holds reliably.
7/16" x 1/8" N42 Neodymium Disc Magnets (48 Pack)
| Size | 7/16" dia. x 1/8" thick (11.11 x 3.18 mm) |
|---|---|
| Grade | N42 (also available in N52) |
| Pull force | 5.4 lbs per magnet |
| Coating | Nickel-copper-nickel (Ni-Cu-Ni) |
| Max operating temp | 176°F (80°C) |
Size, grade, and quality all matter
Grade alone won't tell you whether a magnet will work. N42 describes the material's strength, not the strength of the magnet in your hand. A tiny N42 disc and a 7/16-inch N42 disc are the same grade, but only one will hold a cork ledge and an adult gecko to the side of a tank. Size turns the grade into usable pull force, and quality keeps that pull force the same on the 500th magnet as it was on the first.
That's why the 7/16 x 1/8 inch N42 disc is such a good starting point for this kind of build. At 5.4 lbs of pull force per magnet, a few of them give a mount plenty of holding power, and the 1/8 inch profile disappears into a printed bracket. Matt's rule of thumb is that N42 in this size holds through 1/4 inch of material, which covers most glass terrariums.
Keep in mind that rated pull force is measured with the magnet in direct contact with steel. If you put a sheet of glass between two magnets, that gap reduces the holding force, so thicker walls need more magnets. If your enclosure has extra-thick glass or you're mounting something heavy, step up in size first, to a larger diameter or a thicker disc, and use more magnets per mount. Moving up to a grade N52 magnet adds strength in the same footprint, but a bigger magnet usually buys you more than a higher grade does. Our full disc magnet range lists pull force for every size, so you can compare before you commit to a design.
Quality is the part people notice last and appreciate most. Consistent plating, accurate dimensions, and strength that actually matches the spec are what let Matt build to the same tolerances every time, and what keep a mount from being the weak point in someone's enclosure.
What Holdfast Habitats customers are saying
The magnets come up again and again in Holdfast Habitats reviews. Here are a few from verified Etsy buyers:
“Hard to find something this big with the extra magnets so it can hold your biggest chonker geckos. Great quality and beautiful look in the enclosure.”
Verified Etsy buyer
“The magnet is great to stick around his tank and is strong enough to hold him up. Really happy and satisfied with the purchase.”
Verified Etsy buyer
“Fits in my tank perfectly and the magnets are strong enough to hold extremely well. I'm excited to check out my frogs hanging out in there through the viewing window.”
Verified Etsy buyer
“Excellent design and strong magnets for my gecko's safety. I love it!”
Verified Etsy buyerIf you want a finished, hand-fit piece for your own enclosure, shop Holdfast Habitats on Etsy.
Tips for making your own magnetic terrarium accessories
Have a 3D printer and an idea for a ledge, feeding station, or plant holder? The same approach works for DIY builds. Keep a few things in mind:
- Start with size, not just grade. A 7/16 x 1/8 inch N42 disc at 5.4 lbs of pull is a proven starting point for terrarium mounts. Measure your enclosure wall, and if the glass is thicker than about 1/4 inch or the piece is heavy, move up to a larger diameter or thicker disc before you worry about grade. Use at least two magnets per bracket so the mount can't spin.
- Check polarity before you glue. Mark one face of each magnet and test every pair before fixing it in place, so the inner and outer brackets attract instead of repel.
- Seal the magnets in. Terrariums are humid and get misted daily. Embed magnets fully inside the print or cover them with a reptile-safe sealant so the nickel coating isn't exposed to constant moisture.
- Keep magnets away from animals. Never leave neodymium magnets loose inside an enclosure where an animal could swallow one. Fully enclosed magnets solve this and look cleaner too.
- Mind the heat. Standard N42 magnets are rated to 176°F (80°C). Keep mounts out of direct contact with heat lamps and basking bulbs.
Frequently Asked Questions
Will neodymium magnets hold through terrarium glass?
Yes. Glass isn't magnetic, so two magnets on opposite sides of the glass pull toward each other and clamp together. Holding force drops as the glass gets thicker, so what matters is the combination of magnet size, grade, and how many you use per mount. Holdfast Habitats uses 7/16 x 1/8 inch N42 discs, which hold through 1/4 inch of material.
What size magnet does Holdfast Habitats use?
Holdfast Habitats uses 7/16 x 1/8 inch N42 neodymium disc magnets, rated at 5.4 lbs of pull force each. It's a good starting point for terrarium mounts: enough diameter for real holding power, slim enough to sit flush in a bracket.
Is a higher grade like N52 always better?
Not necessarily. Grade describes the strength of the magnet material, while size determines how much of that strength you actually get. A small N52 disc can hold less than a larger N42 disc. For most projects, choose the size that gives you the pull force you need, then consider a higher grade if you want more strength without changing the footprint.
Do magnetic mounts work on PVC or acrylic enclosures?
Magnets work through any non-magnetic material, including glass, acrylic, and PVC. What matters is thickness. Measure the panel, and for walls thicker than about 1/4 inch, step up to a larger magnet size, add more magnets per mount, or move to a higher grade.
Are magnets safe to use in a reptile enclosure?
They are when they're fully enclosed in the mount. Never leave loose magnets where an animal could reach or swallow them, and seal magnets away from moisture in humid setups.
Can I buy magnets in bulk for my own product line?
Yes. Volume discounts are built into our product pages, and we can put together a custom quote for larger or recurring orders. Contact our team and tell us what you're building.
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