NickSplat is a programming block on TeenNick that airs Nickelodeon shows from the 1980's and 1990's. It began in 2011 as The 90's Are All That, and was re-branded as The Splat on October 5th, 2015. The Ren & Stimpy Show was one of the first shows on the block, airing from 2011 to 2012. After re-runs ended for a while, the show began airing as part of special holiday blocks only, until the show returned to the block on its re-brand as The Splat on October 5th, 2015. The show is still currently re-running on the block. For some strange reason, the show is rated TV-G on NickSplat, despite it being rated TV-Y7 on Nickelodeon. Because of this, many episodes (including "Sven Hoek" and "Dog Show") were never shown on the block for being too inappropriate, or too violent for younger viewers.
Five months later, the series returned to the block on January 22, 2018, and airs every night at 3AM until sometime in April 2018. It is likely that The Ren & Stimpy Show is no longer rerun on Nickelodeon due to the news about John Kricfalusi's sexual allegations back in March 28th, 2018.