`toEventually` custom timeout in Objective-C?

How do I write the following in Objective-C?

// Swift

// Waits three seconds for ocean to contain "starfish":
expect(ocean).toEventually(contain("starfish"), timeout: 3)

Poking around at ObjCMatcher.swift, it seems like Nimble doesn't support custom timeouts in Objective-C. I think it should. Thoughts?