Black Tank Tips 💩 We flush our trailer black tank at least once a week, more often in hot weather. 💩 We use the Rhino Blaster to make it easier. 💩 Use a water meter so you don’t overflow your tank. 💩 Set a timer as a backup. No one wants a toilet waterfall in your RV. 💩 Add an enzyme-based tank treatment after flushing like Unique. 💩 Use a tank cleaning product periodically to break down build-up. Comment if you want links for the water meter or Rhino Blaster. We've lived in our 5th wheel