Zoo Med Laboratories AZMMAL Mopani Wood, Large, 16 to 18-Inch Mopani Wood 679650. Miscellaneous Aquarium Manufacturer: ZOO MED LABORATORIES INC Manufacturer part number: MA-L Zoo Med Laboratories opani Wood A beautiful two color African hardwood for aquariums or terrariums One of the hardest and densest woods available; sinks immediately in aquariums and unlike driftwood, will not rot All natural wood products leach tanninswhich discolour water and reduce pH levels. Soak wood in seperate container to get rid of extra tannins