Feeding

Many species of tarantula will thrive nicely on a diet of varied insects, these can normally be found in most pet stores. For example: crickets, hoppers, mealworms and for the larger species locust or a pinkie mouse. Many insects may be collected from the garden during the summer months, such as moths, caterpillars, beetles and even earthworms. Care must be taken when feeding your spider with beetles or caterpillars since some species of these insects can have spiny appendages which could cause harm to your spider.

 
Some insects which are readily available and may be purchased from pet stores.
WHEN COLLECTING INSECTS FROM THE GARDEN ONE MUST BE AWARE THAT ANY INSECTICIDES WHICH THE INSECT MAY HAVE COME INTO CONTACT WITH COULD HARM YOUR SPIDER.
It is difficult to say how often you should feed you tarantula since there are many size differences. Most adult tarantulas require feeding once to twice weekly and two to three insects should be given each feeding session. Larger spiders will require feeding on a more regular basis for example a Goliath Bird Eater (Theraphosa leblondi) will eat several locust each day, it is therefore advisable to breed locust when keeping a large species of tarantula.
Tarantulas are not greedy creatures and will not overeat and stuff themselves until sick but they will only eat the amount they require and no more, you will therefore get used to your spiders eating habits. If your spider decides it is not hungry DO NOT leave the insect in the spiders container as the insect could annoy your spider and possibly cause it harm. Try to vary your spiders diet as much as possible and supply fresh water daily.
A tip to keep your crickets alive is to feed them and give them water. Special insect foods are available but I have found that fish food does the same job, it also provides you spider with the vitamins it requires and is less expensive. If you are like me and keep fish also it is an added bonus. If you intend to go on holiday then feeding your spider is not a problem since your spider will survive without food for a couple of weeks. In the wild tarantulas can go without food for quite a considerable length of time sometimes months on end but this should NEVER happen in captivity.