You could try silicon pipes instead of the usual plastic ones. They are more flexible anyway so selecting the correct size to push onto t-piece ends means a slightly smaller bore can be used to get a tight seal. Their flexibility means they are easier to push on. They are also less prone to furring up inside. We used them in the cigar factory in the pumped adhesive systems. You can also get a version that is bio resistant in that it increase further the anti microbial/algae/muck build up.
