There are a lot of different ways to modify a tlf for pellets. The first way i tried was to simply add the knitting mesh to the bottom and top plates. The problem I found was that I needed a lot of flow to get them to tumble. The pellets toward the outside of the reactors would tumble but none toward the center. I was using a maxijet 1200 and was sourcing out a larger pump for more flow.
Here is a video that I found. It is a mod for a tlf 150. So my mods are similar.
http://youtu.be/SsNDrSfOXK8
I glued my knitting mesh to the upper plate then glued the acrylic down tube to the upper plate. Attached the elbow to the top of the upper plate using a small piece of acrylic rod that was included. Glued that joint. And attached it to the removable inlet pipe.
Note: flow valve must be on the input hose. Otherwise pellets everywhere inside the reactor.
Voila. Im only using a small amount inside my reactor so I only need 1/4 - 1/3 flow on my maxijet 1200
I will post my pics once I upload them to my laptop.
Mike