YiDeGe liquid ink, started in 1865 by XIE Songdai, YiDeGe’s customers ranging from famouse statemen and fine artists. It is absolutely top one Chinese liquid ink brand.
How to use:
Never pour used ink back to the bottle.
If frozen, the ink is still good to use after being put back to the room temperature.
Yidege brand ink can be storage for years even after opened. The only issue of opened ink (after years) is turning to thicker. Just diluted by clear water and use a brush to even the ink and water.
For the better result of dilution, mixing thicker ink and water in an ink stone, then grounding by an ink for stick for couple minutes.