I got the RODI buddie...I wouldn’t actually call it portable, but it’s set up so that you don’t need permanent placement, mine sits on top of my dryer while running, and taken to a shelf when not running. For the value, and price of replacement parts the 100gpd set up w the DI add on for a total of 88 on Amazon was well worth it for me@ridgeburyreefer - what portable unit do you have? I didn't know they existed in that configuration.