[fantasy_aquatic]

adding ketapang leaves to the aquarium is an attempt to simulate the natural "black water" environment of most tropical fishes.
Black water has a distinctive brownish tea colour and contains many dissolved organic materials suc as humic and tannins.
Dried ketapang leaves will help to release these organic acids into the aquarium water.
these would turn lower the water pH level, absorb harmful chemicals and create a soothing and calm environment for the fish.
Peat and decaying driftwood, which are also rich sources of humic acids will also be helpful additions to the aquarium.

the ketapang tree is a big 'pagoda-shaped' tree with distinct tiered brances. The tree originates from the malaysia region.
The bark, fruit and leaves of the tree have traditionally been used to treat various ailments, from skin disease, dysentery, headaches to colic in children

Ketapang ( Terminalia catappa ) is also known by the following common names, tropical almond, badamier, java lamond, amandier de cayenne, wild alomond, indian almond, myrobalan, malabar almond, singapore almond, huu kwang, sea almond and kobateishi.
The tree is known to produce a poison in its leaves and sap to defend itself against insect parasites. When the dried leaves falls into the river, they leave a strong brown dye that is full of organic acids like humic acids and tannins.

Humic acids and tannins may be usefull for inhibiting many types of bacteria including cyano-bacteria. Humic acids also detoxify heavy metals. Humic material and detritus in the aquarium also rapidly absorb and detoxify many chemicals, including zinc, aluminium and copper.

HUmid acid is the end product of microbial degradation of plant and animal debris and is an important constituent of fertile soils. it contains sulfur, nitrogen and phosphorus in varying amounts. Also present are metals such as calcium , magnesium, and zinc. tannins, lignins and fulvic acids, are sub classes of humic acids, which tint the water yellow