What size water hosing is used? Andrzej February 13, 2018 11:14 Updated Follow We use 8mm internal diameter hosing (around 10mm external) for all of our water lines. Related articles Setting up your HOTTAP HOTTAP User Guide Why are your prices higher than competitors? Can I just use the HOTTAP Outing filter in the creek? HOTTAP Outing User Guide Comments 0 comments Please sign in to leave a comment.