Tiger Wood is an ideal centerpiece decoration for aquarium. The size and shape vary piece by piece. For larger piece is typically heavy enough to sink on its own. For smaller piece (lighter-weight) takes a few days to sink
Treating Tiger Wood is required
Soak the wood few days to allow excess tannin to leach out. The tannin will not harm your aquarium inhabaitant, but it help lower the pH.
Or boiling wood help sterilizes the driftwood, killing algal or fungal spores. Approx. boiling time is 20-30 mins.