Not only do ants eat termites, but ants are one of the primary predators of this wood-eating insect. Sometimes ants help control termite populations depending upon the relative size of the two colonies and other available food sources.
Spiders also prey on termites, but this most typically occurs on an individual basis when a termite becomes trapped in a spider's web. Microscopic roundworms called "nematodes" also feed on termites, but this process is different from ants and spiders. Nematodes, which are parasites, are the most common animals on the planet. A roundworm gets inside a host organism, such as a termite, and feeds off of it.