Ketapang or Sea Almond or Indian Almond or Terminalia catappa leaves are known to most, if not all Asian breeders of blackwater tropical fishes, to be one of the best water conditioners to promote healing and breeding. They are known to have antibacteria and antifungal properties. Bettas are known to be induced to spawn by just putting a few of the leaves into their tank. Fish suffering finrot or injuries (such as spawning injuries) will definitely benefit from having the leaves in their quarantine tank. But they can be used for the usual aquariums too.
When soaked in water these leaves will leach a strong brown dye that is full of organic acids like humic acids and tannic acids. These are useful for inhibiting many types of bacteria as well as to detoxify harmful heavy metals found in the aquarium.
It is well-known, for example, that show bettas kept in a 1 gallon tank will require water changes every 2 or 3 days if mature untreated water is used. But when Indian Almond Leaves are used the water change routine can be stretched to a week. Also, tubifex worms kept in tap water or even matured water will experience necrosis and stink within a day or two, whereas if they are kept in water treated with Indian Almond Leaves (or extract), they will continue to thrive for up to a week without the water fouling up or becoming smelly.
Remember that no two Indian Almond Leaves are the same. Different Indian Almond trees produce different quality leaves at different times of the year! Indian Almond Leaves come in different sizes, shapes, thickness and colour. Some are large, others are small. Some are red or dark coloured when fresh, others are yellow or green. Some are very thin and crinkled when dried, others are thick and leathery. Some are broken or holie when collected, others are whole and perfect.
For this reason, price should not be the only consideration for what to buy and whom to buy from.
Since these leaves are a consumable, the appearance of the leaves may not be of utmost importance. However, unless the leaves are sold by weight, it is usually safer to go for graded leaves. Otherwise you may end up with leaves of different size and quality (in terms of colour, tickness, age, etc).
There are generally two ways of grading. One is to grade the leaves by size. For example, all leaves larger than 7" may be classified as Grade A, whereas all smaller leaves are classified as Grade B.
Another approach is to grade according to whether the leaves are whole, and has holes or tears, as well as the colour and thickness. Under this grading system, we could have 5 categories of leaves:
Grade A Large (7"+), Grade A small (5-7"); Grade A baby (3-5"); Grade B Large (7"+); Grade C (anything else still usable).
It is generally safer to buy leaves that are graded in this way. Choose the sizes according to your needs. For example, if you keep bettas, small and baby leaves may be more suited for your use, whereas if you keep arowanas or plecos, you might prefer the larger leaves.
If you use a lot Indian Almond Leaves, and normally use them to make blackwater rather than leave them in the tank (as you might want to do if you are spawning bettas), then you might want to consider Grade C leaves.
Do not buy leaves that are harvested fresh from the tree. These leaves are not the kind of leaves that would be found in blackwater streams. The leaves found in blackwater streams are naturally fallen ones.
Prefer darker leaves to lighter coloured leaves. Some Indian Almond Trees produce only yellow-coloured matured leaves, others will produce red-coloured leaves. If you have a choice, go for the darker coloured leaves.
Also, take note of the difference between weather beaten leaves, and leaves that are freshly fallen and dried. Weather beaten leaves may tan the water very quickly, but most of their beneficial properties would have been leeched away due to rain water washing over them. Freshly fallen leaves tend to take longer to tan the water (about 3-4 days). These leaves will release their beneficial properties like slow-release medicine capsules.
Note the difference between shade dried, sun dried and flat dried. Flat dried leaves are are usually graded as A+ as they are usually produced with the best looking leaves that have freshly fallen from the tree, and take a lot more work to produce. When buying flat dried leaves, make sure they are naturally fallen when matured rather than harvested from the tree. Shade dried and sun dried leaves have very little difference. But make sure they are crispy dry or they may grow mouldy in transit. Some believe that sun-dried leaves are less likely to have harmful bacteria etc. But take note that it is unlikely that any terresterial bacteria found the leaves would survive when immersed in the aquaria. Others believe that shade-dried leaves have most of their benefiical properties locked in. When in doubt, check with your supplier how his/her leaves are prepared.
A few sellers would sell leaves that are not completely dry. If you receive leaves that are not completely dry, make sure you dry the leaves in the sun (or at least in a dry place) before using them. This is because fresh leaves will tend to pollute the water in the tank; and also because these leaves will become mouldy very quickly unless they are dried. Leaves that have become mouldy would loose their efficacy.
Finally, do make sure that the leaves you buy have been thoroughly washed and dried. The leaves should be washed over running water with a soft scrub-brush. They should not be soaked as some of the benefial properties would otherwise be lost. Washing removes not only dirt but any foreign chemicals that may have fallen on the leaves. Do not assume that if you are buying leaves from a third world country that there will not be a problem with pesticides. Remember that many third world countries do mosquito fogging. This is one reason why you should buy only leaves that have been washed and dried. But to be safe, do remember to rinse your leaves before putting them into the aquarium.
Indian Almond Leaves may either be shipped in a box or simply in an envelope. When they are shipped in an envelope, postage cost should be lower, but damage to the leaves (crushing) is quite likely. If you like your leaves to serve also as part of the deco in your tank, do not choose this option unless you do not mind leaves that look battled. Leaves that are shipped in a box will usually incur a higher postage. But as the leaves are quite light (about 2 grams for a large leaf and 1 gram for a small leaf), the postage would not be very much higher unless the box is very heavy.
b. Leaves that are stored for too long especially in tropical humidity will begin to loose their efficacy after 6 month or so due to degradation of the leaves. For this reason it is best to purchase leaves that have been freshly collected, washed and dried. If in doubt, do check with your supplier, how long it has been since his/her leaves have been collected and stored.
c. Leaves which are thoroughly dried will last a very long time in temperate or dry weather condition, so if you use these leaves regularly, it is advisable to buy a bigger portion to save on postage.
d. Some suppliers of Indian Almond Leaves would flatten their leaves by using a hot iron. This is actually a controversial practice as hot-ironing will destroy some of the beneficial properties in the leaves. You can easily confirm this assertion with a simple experiment. Take a naturally dried Indian Almond leaf, smell it. There should be a sweet smell. Iron it with a hot iron. Smell it again. This time it will smell different. You can try the same experiment using other leaves if you do not have access to Indian Almond Leaves. If you like flat leaves, make sure that they are dried between papers. These take a lot more effort to produce, but the leaves will look smoother, more beautiful and smell like naturally dried leaves. These are the true A+ leaves. Hot ironed leaves, on the other hand, will look quite crinkled though flat; and they will smell cooked.
e. If you are buying leaves from local stockists or resellers, it may be good to enquire about the source of the leaves. It is always safer to buy leaves that originated from a reliable supplier which grades his leaves and understands the importance of making sure the leaves are matured, washed and dried; and safe to use for your precious fishes.
Grade A+ (Flat dried) Leaves