Tarantula caresheet

Mexican Red Kneed Tarantula _Brachypelma smithii_

Mexican Red Kneed Tarantula (Brachypelma smithii).

Before you buy a tarantula you should think about the conditions it will need to live a long and healthy life. Many tarantulas die in the first few days because their new owner hasn't prepared a suitable home for them. First decide what you want to buy because a small spiderling will obviously require very different accommodation to a full grown specimen.

I will assume you are buying a medium-sized tarantula in which case you will need to provide the following.


Pet shops will sell suitable tanks in glass or plastic and the size should not be less than about 25cm by 20cm by 20cm high. If you want to create a tank that tries to provide natural conditions (for example rain forest with leaf litter, logs etc.) then you will need a much larger tank, but you won't see your spider very often! I would suggest that you begin with the simple tank without unnecessary contents so that you can watch your tarantula's activities.

Substrate (Ground cover)

A 5cm layer of Vermiculite should cover the bottom of the tank and a thin layer of chipped bark or cocoa fibre placed on top of that. These can be purchased from most garden centres and should be kept damp to keep up the humidity levels in the tank. Potting compost should not be used as it really needs to be sterilised and changed frequently. If your tarantula is a terrestrial species that likes to dig then you may need up to 15cm of substrate and a larger tank.


A temperature of 21-24°C is required for most of the tarantulas that you should buy as a beginner. If you have a centrally heated room which stays at that temperature all the time then you won't need extra heating during the winter, but you will between spring and autumn when the heating is switched off.

A good pet shop that sells reptiles and spiders will have a variety of thermostatically controlled heating devices including underground cables and heating mats. Tell them the size and type of tank that you are using and they will recommend a suitable heater for you. An alternative is a seed propagator which can be purchased from garden centres. You can keep your tank inside it. Red light bulbs are not suitable for heating spider tanks.


The humidity in the tank should not be less than 50-60% and you should buy an accurate humidity gauge to put inside the tank. If the humidity drops below 50% your tarantula may die during its next moult. You can keep the humidity high by dampening the substrate. Misting the tank using a plant mister can also help, especially for arboreal species, but be aware that the water droplets can evaporate quickly. If you are using a plant mister then you should make sure that it has been washed thoroughly if it's been used for any plant fertiliser or other chemicals. Also, keep a check on the tank to make sure no mould develops.


Crickets and locusts are usually available from pet shops that sell tarantulas and reptiles, and you can try other livestock too such as wax worms. A tarantula of about 3-4cm in body length will eat 2-3 crickets per week but they will not over eat so any crickets not being eaten may indicate that you are overfeeding your tarantula or it is preparing for a moult.

If you keep live food for your tarantula then you should also ensure that the live food is kept in appropriate conditions (adequate space, correct temperature and humidity and access to food and water).


Water is vital to your tarantula. It can survive for weeks without food but quickly die without water. A small container such as a coffee jar lid half-full of water will provide drinking water and help keep the humidity up.


As your tarantula grows it will moult (shed its skin in a process called ecdysis) regularly, 2-3 times a year in the case of the half grown individual. Signs of an approaching moult are darkening of the colour and the spider will stop feeding.

When feeding stops, remove any live food in case they irritate the spider, or worse, nibble it while it is helpless during the moult. Normally the spider will turn on its back to moult and lie still in that position for several hours. Do not disturb it in any way at this time as activity may prove fatal. Feed it about 7-10 days after moulting when its new skin has hardened.

Suggested species

For your first tarantula you don't want an aggressive, difficult to keep or very expensive specimen. The following are ideal species:

Additional considerations

Urticating hairs

Most species of tarantula possess urticating hairs. These hairs are a defensive hair that can cause itching/irritation of the skin or more severe problems if hairs enter the eye. Care should be taken when handling tarantulas or cleaning out their enclosure. Tarantulas may also rub their back legs across their abdomen to flick hairs upwards if they feel threatened.


All tarantulas are capable of biting (since this is how they feed). Many species are docile and rarely bite as a means of defence but others are more aggressive. Biting is often a last resort and different species have different threat behaviours (for example, raising the front pairs of legs, showing their fangs or hissing by rubbing their chelicerae together) which indicate that they feel threatened. It is important that you can recognise these behaviours or, better still, avoid doing anything that makes your tarantula feel threatened.

You may also find our page on Arachnids interesting.

Remember: it is important that you know the needs and requirements of your pet before you obtain the animal. You should never, ever obtain an animal before researching its needs and preparing the housing and conditions.

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