This past Thursday's episode of Impact Wrestling on Pop TV garnered 284,000 viewers. It was down 7% from last week's show, which averaged 305,000 viewers.
As far as first run episodes, it was the least watched episode since the June 14th episode, which averaged 210,000 viewers. However, that episode was plagued with technical issues, and a replay for that episode added 117,000 viewers, bringing the total audience for that episode to 327,000 viewers.
Taking into account only first run episodes, it was the 9th least watched episode since the show moved to Pop TV. However, Pop TV aired Impact replays until early April. If you were to take into account the total audience for an episode (first-run + replay), then it was the least watched show since the move to Pop TV, and the second least watched episode in history since the show debuted on Spike TV in 2005.
The record for the lowest total audience for an episode of Impact (since Spike) remains the November 11, 2015 episode on Destination America. That episode averaged 202,000 viewers for the first-run episode and another 78,000 viewers for the replay, bring its total to 280,000 viewers.
Source: Showbuzz Daily