From what i research, Nano tanks are harder to maintain due to the smaller volume of water. The water parameters tend to be not so stable and not easy to cycle. Thus frequently water changes is advisable for nano tanks.
If your colleague don't bother with the maintenance of the nano tank, chances are the water parameters have gone way too drastic for fishes to survive. Imagine all the fish shits accumulated and dead plants making ammonia level shoots up very high.
Wood soak in water will normally give out(leach) Tannins. Tannins color the water, light brownish like tea. They also lower the pH alittle. So some people will actually soak the wood for a few weeks or more. It will not totally remove all the tannins but it will help to reduce them by soaking them first. Soaking the wood first also helps to see if there are any un-welcome guests that stick to the wood.

Bookmarks