One of the original and simplest methods was to dissolve a couple of sachets of gelatin powder in warm water. Then some dry expander’s were added to a large sandwich bag, followed by the water. The bag was then tied off and left overnight, occasionally rotating them. In the morning the pellets would have expanded and taken on the gelatinous water, and because some of the air had been taken out of the bag, they remained nice and firm.

The best pellets for this are actually not expander’s, but Cornish bagging pellets sold from whiteacres, they are unique in as much as they take on water without breaking up and if you soak them just right, you don’t need any gelatin at all, as they stay nice and rubbery. The best thing is though, that they all sink without being pumped or squeezed.