I'll give you a tip - take the ends off the Ionics vessel, get yourself some 3inch downpiping, it might be 4 inch, can't remember) and cut it to the same length as the ionics vessel (30inch) and the ends you kept over from the Ionics vessel will fit really nice and tight, you may need rubber o-rings on each end but its so simple its scary.
Total cost - less than £10!!
You owe me a pint!!