sure, they'll happily gobble up ants.
idk if venomous food is a good idea far as the spiders.
toads will eat nearly anything they can stuff in their face.
i've been buying fruitfly cultures from josh's frogs.com for my 250 toadlets; theyre thriving on hydeia flies but if yours are really tiny get the melanogasters.
good prices, toadlets love the flies, great service.
ants probly dont have much nutritional value, either.