Can I collect replies to tracked hashtags using the Streaming API?



I’m cooking up a small service to allow people to post ideas on Twitter using a specific hashtag, #2025ideas, and inviting their followers to comment on the ideas.

I have no difficulty setting up a client to track the hashtag #2025ideas and collecting tweets using it as they come in. But I’m not sure how to be notified when someone’s follower replies to one of these tweets but doesn’t use the same hashtag in his or her reply.

So say user 123456789 posts “Flying cars with autopilot #2025ideas.” My client gets a notification.

Then user 987654321, who follows the origin user, replies with “And those cars better have coffee makers!” I want that tweet too, but it’s unreasonable to expect that user to know to use the hashtag.

The Streaming API has a replies parameter, but it appears to only work for streaming clients that follow a specific user or site. Does anyone know how I can do this?

I could, of course, make separate occasional REST calls to the original tweet looking for replies, but this strikes me as highly inefficient and unscalable.