4mm OD (Outer Diameter) silicone tube 50cm long can be cut to size to accommodate the collets and connectors to prevent the tube from slipping in the pump head due to this method of pumping. Please refer to the manual for more details of how and why, or even drop me a message.
This 4mm OD tube fits my pump head supplied here. I use 4mm OD tube so I can fill my tiny sample bottles. If you require a larger OD tube (e.g. to increase fill speed) then that can be sourced in various places and I can certainly assist with that if you need it. Of course, if you use a larger tube OD, then you would need a different pump head. Drop me a message and I can provide a pump head to fit.
I advise too that to aid in preventing both cross-contamination and for easier cleaning use a separate tube per liquid product.