User blog comment:Miskos3/Fairy Tail Episode 255: Tartaros arc: Steel, Review/@comment-7405046-20151017210814/@comment-7418318-20151017211508

In the manga the water disappeared, due to Torafuse being defeated, rather than anything directly from Gajeel (just like Aquarius' water disappeared, when she was sent back to the Spirit World after her key broke).

I have no idea why in the world the anime team chose to animate it like that... or why it turned into sparkles for that matter.