Guide to Brewing your own Catappa Blackwater Extract | Learn about benefits of tannins in Terminalia catappa leaves

How to brew your own catappa Blackwater extract

Published by Amy Lim October 2, 2011

Commercial blackwater extracts tend to be very expensive. This guide provides some easy to follow steps for brewing blackwater extract using Indian Almond (Terminalia catappa / ketapang) leaves.

Some fish species, such the betta, gourami, killifish, and arowana, call their acidic water environment "blackwater", which refers to a specific color of water. The tannins in driftwood, peat moss, and dead leaves give the water in these ecosystems a distinctive amber or tea hue. As the seasons change, Indian Almond (Terminalia/Ketapang) trees will drop some of their leaves, and occasionally they will drop nearly all of their leaves. Where there are Indian almond trees, the blackwater stream, marsh, or pond will likely be littered with Indian almond leaves. In other words, the tannins in the dried Indian Almond Leaves that have fallen into the water give the blackwater its distinctive hue.

Tannins aren't the only thing that can be drained from Indian almond leaves; research has revealed that many other healthy compounds can be extracted from these leaves as well.

Dr. Robert J. Goldstein (not the podiatrist-want tobe terrorist from Florida; but the North Carolina aquarist and environmental consultant who produced multiple books on fish-keepings) writes in his 2002 study titled "Water Conditioners and Additives," in reference to Terminalia catappa tree leaves:

In traditional medicine, the big leathery leaves are used to heal infections, indigestion, and other ailments. The tea made from the water extract is quite potent medicinally. To create a flat surface for the bubblenest and to leach chemicals that protect the fry from illnesses, Betta breeders in Southeast Asia often add a dried leaf. Detritus from the rotting leaves can be used to cultivate infusoria that are resistant to extracts, which can then be fed to the infants. Notable among the 35 aromatic (ring structure) compounds discovered in these leaves were benzene-acetaldehyde, acetones, and sabinen-hydrate. The first is highly antibacterial, and a number of the other 35 disrupt the membranes of microorganisms.

And he adds: "So these leaves are not simply sources of stains and tannins and other acids as we would get from oak or hickory, but rich in many other kinds of complex and highly effective chemicals with a wide range of physiological and antimicrobial effects."

For this reason, blackwater extract made with Indian Almond Leaves can actually be more effective than those made with peat moss alone.

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To brew blackwater extract, follow the following steps:

1. Collect or purchase a bag of Indian Almond Leaves. If you purchase, Grade C leaves will be good enough, but remind your supplier not to clip off the leaf-stubs if he routinely does so.

2. Wash the leaves over running water with a stiff brush if they are not already washed. If they are already washed, rinse the leaves.

3. Get a large pot (preferably clay pot, else stainless steel, but certainly not copper) which is large enough to contain say 2 gallon of water.

4. Put about 50 (or more) leaves for each gallon of water the pot can contain.

5. Fill with clean water (preferably with chlorine and chloramine removed).

6. Weigh the leaves down with a chemically inert stone (e.g. granite).

7. Let the leaves soak in the pot for a day.

8. Boil the pot for 15-20 minutes.

9. Leave it to cool and soak for another day.

10. Boil one more time for 10-15 minutes.

11. Leave to cool. The water in the pot should be as black as thick coffee and very fragrant.

12. Filter the blackwater extract through a coffee paper filter (to trap detritus or any other insoluble matter).

13. Store the liquid in sturdy plastic or glass bottles.

14. Refrigerate or keep somewhere cool.

Dosage & Improvements

Dosage will be 1 ounce for 1 gallon of water in the Betta tank. Use your discretion for larger tanks, but do not use more than 1 ounce for 1 gallon of water.

To improve efficiency you may also add anti-chlorine and chloramine into it, but make sure you calculate how much to add so that when you use 1 ounce of your blackwater extract, you will be able to treat 1 gallon of water (to rid it of chlorine and chloramine).

Refrigerate or use standard canning process to give your extract a longer shelf-life.


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Guide to Brewing your own Catappa Blackwater Extract | Learn about benefits of tannins in Terminalia catappa leaves
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