Step 3: Tank Type
Some tanks come with a welded steel bottom cap. These could be a challenge. (Not saying it couldn't be done with this type tank but, the separate plastic bottom does a nice job of covering the hole in the bottom of the tank.)
Remove the plastic Bottom Cap. This cap is held in place with a small dab of hot melt glue. If the tank is cold, the glue becomes brittle and will allow the cap to pop off easily. The tanks used here, were outside this winter so there was no trouble removing them without damage.