Does anyone have a tried and true compost unit that was made perhaps out of free wooden pallets/skids? My husband is going to look around and see if anyone wants to part with them for free. We need to get a compost pile made that will work for next to nothing,be properly maintained (airated), temp where it needs to be,keep animals away, a well balanced bin. We live in the tropics . We get alot of rain,do not have dry brown leaf debris to add. Any suggestions on how to build one and maintain one here in the tropics? We found a few earthworms in our garden . Do we add some worms to layers in the bin?