Indian Almond (also known as Ketapang or Tropical Almond or Sea Almond or Seemandelbaumblatter or Terminalia Catappa) leaves are becoming very popular amongst fish keepers/breeders, not just in South-East Asia but around the world, as a natural medicine and water conditioner for aquarium use.
 

We have always used Indian Almond Leaves for conditioning and care of our Bettas. They are believed to aid the fish in a number of ways, they increase fertility, health, and vigour. Reduce Ph in water, aid in the recovery of diseased/damaged fish and the tannin quickly colours the water.
 

Aquarists also use Indian Almond Leaves to mimic the natural conditions of their fish in their aquaria. Simply adding Indian Almond Leaves ( IAL ) to your aqurium will release compounds by the leaves which alter the chemistry of the water, making the aquarium more similar to the habitat from which the fish hails. 
 

As well as bettas, these leaves are also ideal for discus, gouramis, killiefish, tetras, arrowana’s, angelfish, South American dwarf cichlids, corys, plecos, some rasboras some cat-fishes and crustaceans and shrimps just love to chew on them. They are also ideal as litter in vivariums