Fine Fir Bark — Soil Amendment & Substrate for Bioactive Vivariums & Dart Frog Setups Description: Fine fir bark (small-sized pieces) is a soil amendment and substrate commonly used in the bioactive and dart frog hobbies. This fir bark is a critical component of original ABG mix. Why keepers love fine fir bark: Critical ABG component — A foundational ingredient in original ABG substrate mixes Moisture retention — Retains moisture to help stabilize humidity in the substrate layer Plant growing medium — Provides structure for plants to root into Naturally mold resistant — Holds up well in humid bioactive setups Multi-use — Commonly used for geckos, reptiles, dart frogs, and other bioactive builds Best for: dart frog vivariums, tarantula enclosures, planted terrariums, gecko setups, and any bioactive build using ABG or similar substrate mixes.