i got this driftwood for my 125g planted rainbowfish tank. 2 pieces are mopani and the other branchy one is mangrove root. My questions are is mangrove root safe to put in aquariums? Also how long would it take to get most of the tannins out of the pieces of mopani. The one on far left is over 20 inches tall and the middle one is a pretty thick piece of mopani. I can not boil them they are too big and heavy. I'm concerned about the tannins lowering my ph. My ph is 8.0-8.2 gh 12 kh 10. I know people use driftwood for softwater fish but every rainbow tank i see has driftwood in it. Thanks for any help