Mexican Red Knee Tarantula
Brachypelma hamorii
1. Deep Soil & Low-Ceiling Safety Setup
2. Two Great Ways to Set Up Your Habitat
Sizing the Tank: Slings vs. Adults
Putting a fingernail-sized baby ('sling') in a giant 10-gallon tank makes it impossible for them to find dinner:
Option A: Spiderlings ('Slings' Under 1.5")
Keep in a vented sling vial or micro acrylic cube (about 3–4× their legspan wide) with 2" of soil, a piece of moss, and a clean tattoo-ink cap or bottlecap for water.
Option B: Juveniles & Adults (2" to 7"+)
A 5- to 10-gallon glass or acrylic enclosure filled halfway up with 4–6" of packed reptile/invertebrate soil and a curved cork bark starter cave.
Ground Burrowers vs. Tree Climbers
Make sure your setup matches where your spider actually lives in nature:
Option A: Ground / Burrowing (Curly Hair, Red Knee, Arizona Blonde)
Wide floor space, deep 4–6" soil for bulldozing, and low ceiling clearance so a clumsy climber can never take a big fall.
Option B: Tree-Dwelling (Pinktoes, Versicolor, Jumping Spiders)
Tall enclosure with lots of side-wall air holes (cross-ventilation!) and tall cork bark reaching near the ceiling.
To Handle or Not to Handle?
Real talk from our invert team: tarantulas don't get cuddly from being held—handling is mostly for us:
Option A: Hands-Off Display Pet (What We Recommend)
Safest for the spider! Use a soft paintbrush to gently tap their back legs and guide them into a catch-cup whenever you need to clean.
Option B: Sit Flat on the Floor (Calm Docile Species Only)
If you do let a calm Curly Hair or Red Knee walk on your open palm, sit on the floor or bed so a sudden bolt can never mean a fatal drop to the floor.
3. Feeding by 'Booty Size' & The Molting Rule
Best Bugs & Big No-Nos:
Top pick—nutritious and won't bite a spider!
Great hunters—MUST remove uneaten crickets after 24h!
Crush worm heads so they can't hide underground
Wild bugs carry lawn sprays & parasites that kill spiders
4. Four Keys to a Happy, Thriving Mexican Red Knee Tarantula
Watch Out for Wire Mesh
Heavy ground tarantulas have two tiny hooks on each foot that can get snagged in cheap woven window-screen lids. Acrylic lids with drilled air holes are way safer!
Overflow the Water Dish
Tarantulas hate being sprayed in the face with a mister! Instead, just overfill their water dish a little bit once a week so one corner of the soil stays damp.
Itchy Belly Hairs
New World tarantulas kick itchy 'urticating hairs' off their butt when annoyed. Don't rub your eyes after working in the tank, and wash your hands with soap!
Upside-Down vs. Death Curl
Flat on their back = happy molting! Right-side-up with all 8 legs curled tightly *underneath* the belly = dehydrated ('death curl')—put their mouthparts right into a shallow puddle of water!
Bring-Home Shopping Checklist
Tap items to check them off on your phone while you shop at Critter Cabana.
Enclosure & Deep Soil
Water Dish & Safe Tools
Live Feeder Bugs
Complete Reference Notes & Oregon Keeping Guide
Species: Brachypelma hamorii (formerly B. smithi) | Difficulty: 2/5 — Easy | Hardiness: 4/5 — Hardy
Critter Cabana & Gresham Pet Supply — Keeping Your Pet Healthy & Thriving
At a Glance
| Common Name | Mexican Red Knee Tarantula |
| Species | Brachypelma hamorii |
| Origin | Scrublands and deserts of Mexico |
| Adult Size | 5 to 6 inches (diagonal leg span) |
| Lifespan | Males: 3 to 5 years. Females: 20 to 30+ years. |
| Diet Type | Insectivore (Crickets, roaches, mealworms) |
| Activity | Crepuscular/Nocturnal (Terrestrial burrowers) |
| Temperament | Generally calm and docile, but very quick to flick urticating hairs if startled. |
| Handleability | Fair. While they rarely bite, their urticating hairs are highly irritating to human skin, eyes, and lungs. Handling is not generally recommended to avoid stressing the spider and getting "haired." |
| Difficulty | 2/5 — Easy (A classic, beautiful display tarantula) |
| Hardiness | 4/5 — Hardy (Thrives in dry, room-temperature environments) |
Why We Love Them: The Mexican Red Knee is arguably the most famous tarantula in the world, starring in countless Hollywood movies. Their striking black bodies contrasting with bright orange/red bands on their leg joints make them a stunning display animal. Because they prefer dry environments, they spend a lot of time out in the open rather than hiding in burrows.
Housing & Enclosure
Terrarium Setup
- Type: Terrestrial. They require horizontal floor space, not vertical height.
- Size: A 5 to 10-gallon tank is ideal for a fully grown adult.
- The Fall Hazard: Terrestrial tarantulas are heavy-bodied and extremely fragile. A fall from even a few inches can rupture their abdomen, which is fatal. You must fill the enclosure with enough substrate so that the distance from the dirt to the lid is no more than 1.5 times the spider's leg span.
Substrate & Decor
- Deep Substrate: Provide at least 4 inches of a dry substrate like Coco Coir (Eco-Earth), ReptiSoil, or a sand/soil mix.
- Hide: Provide a cork bark flat or a half-log to serve as a retreat.
Environment & Husbandry
Temperature & Humidity
- Temperature: Standard room temperature (70-80°F) is perfect. They do not require external heat sources like heat lamps or pads, which are dangerous and can cook them.
- Humidity: Brachypelma species come from arid environments and prefer it bone dry. Do not mist the enclosure. High humidity and damp substrate will cause them to climb the walls to escape the moisture.
Water
- Provide a shallow water dish at all times. Do not use a sponge in the dish. Sponges harbor fatal bacteria; tarantulas cannot drown in a shallow dish and will drink directly from the water.
Diet & Feeding
- Staple Diet: Live crickets, dubia roaches, and mealworms.
- Feeding Schedule:
- Slings (Babies): Feed 1-2 small prey items twice a week.
- Adults: Feed 3-5 large crickets (or 1 large roach) every 1-2 weeks.
- Note: Brachypelma species are notorious for fasting. They may occasionally refuse food for months at a time, especially during the winter or prior to a molt. As long as their abdomen is plump and they have water, this is normal.
Molting (The Molt Warning)
- When your tarantula is preparing to molt, it will refuse food, become sluggish, and a bald patch on its abdomen will turn shiny and dark black.
- When they molt, they flip upside down on their backs. DO NOT TOUCH THEM OR FLIP THEM OVER. They are not dead. Touching a molting tarantula will kill it.
- Remove all live prey from the enclosure before a molt, and do not feed them for at least 7-10 days after a molt to allow their fangs to harden.
What We Stock & Use in Our Stores
| Category | Product | Notes |
|---|---|---|
| Housing | Exo Terra Breeding Box (Large) | Ideal terrestrial footprint |
| Substrate | Zoo Med Eco Earth (Loose) | Keep completely dry for this species |
| Decor | Zoo Med Natural Cork Bark | Creates excellent, natural-looking hides |
| Diet | Live Crickets / Dubia Roaches | The best staple feeders |
Care sheet compiled by Critter Cabana & Gresham Pet Supply.
Last updated: 2026-08-04
How We Keep Them at Critter Cabana & Gresham Pet Supply
- Oregon Winter Furnace Air vs. Molting Humidity: When Pacific Northwest furnaces kick on from October through April, indoor room humidity drops fast and dries out small enclosures from the top down. Rather than misting the spider or invert directly (which stresses terrestrial species and invites stagnant mold), we keep Mexican Red Knee Tarantula at
50-60% (Dry)by using a deep moisture-retaining substrate bed (ReptiSoil + Coco Fiber + Sphagnum Moss), overflowing the water dish slightly into one corner, and maintaining cross-ventilation. - Safe Room Heating in the Willamette Valley: If your house drops below 65°F on winter nights, never stick a heat pad on the bottom of a burrowing invertebrate tank—they dig down to escape heat and will cook themselves. Use a low-wattage side-mounted heat mat on a digital thermostat or warm the room ambiently to
70-80°F. - Stocked at Newberg & Gresham: At Critter Cabana (Newberg) and Gresham Pet Supply, we stock acrylic and glass invertebrate enclosures, cork bark flats and tubes, bioactive substrates, flightless fruit flies (D. melanogaster and D. hydei), pinhead to adult crickets, dubia roaches, and live Temperate White Springtail and Isopod cultures.
Common Questions (FAQ)
How do I keep my Mexican Red Knee Tarantula warm and humid enough during an Oregon winter?
Target 70-80°F and 50-60% (Dry). When Oregon winter furnaces dry out the air, use a deep 3–5 inch substrate mix of Zoo Med ReptiSoil and coco fiber, keep a shallow water dish filled, and dampen one corner of the substrate rather than misting the animal directly. Never put a heat mat underneath a burrowing invertebrate enclosure.
What size enclosure does a Mexican Red Knee Tarantula need?
An adult Mexican Red Knee Tarantula thrives in 5-10 Gallon Terrestrial with secure ventilation. For terrestrial tarantulas and scorpions, floor space and deep substrate matter most (keep open fall height low so heavy-bodied species cannot rupture their abdomen); for arboreal species, prioritize vertical cork bark tubes and cross-ventilation.
Can I put isopods in a Mexican Red Knee Tarantula bioactive enclosure?
Around molting tarantulas and scorpions, skip protein-hungry large isopods and stick to Temperate White Springtails (or gentle Dwarf White isopods in humid detritivore setups) so a soft, newly molted animal is never nibbled.
Where can I find Mexican Red Knee Tarantula, cork bark, and feeder insects in Oregon?
We stock live invertebrates, tarantulas, jumping spiders, cork bark flats and tubes, bioactive substrates, and gut-loaded feeder insects at our two exotic animal stores: Critter Cabana in Newberg (514 E First St, 503-537-2887) and Gresham Pet Supply (2185 NW Burnside Rd, 503-665-7606).
