Are Indian Almond Leaves Good For Aquarium Fish?


Are Indian Almond Leaves Good for Aquarium Fish?

Have you ever seen a stack of large, dried leaves at the fish store and wondered what they are for? Terminalia Catappa (IAL) is a tree that comes from India and Oceania. It also produces catappa or Indian almond leaves. Its fruits taste like almonds and are used in traditional medicine and herbal teas.

Fruit and leaves of the Indian almond tree

A dried catappa leaf can slowly decompose in aquarium water and create tannins. These plant-based substances gradually lower the pH level and give the water a yellow-brown hue. Many people do not like the tannins naturally produced by leaves and driftwood and use chemical filtration to get rid of the brown tint, but they actually have many uses in the fishkeeping hobby.

What uses are Catappa leaves used for?

If you have sensitive species (like crystal shrimp and certain South American fish) that prefer

Low pH water and low pH water

Indian almond leaves slowly lower pH levels by releasing tannic, humic, and fulvic acid organic compounds. Although they take longer to produce pH buffer chemicals, their gradual effect can be considered safer as they are less likely cause dangerous pH swings. They have a detrimental effect on water chemistry so they are not recommended for high pH fish like African Cichlids or other livebearers.

While some soft water fish don’t require low pH for their normal living conditions, you may be more successful with breeding and raising their fry if you make the water more acidic. Breeders use catappa leaves to raise betta fish (both wild and Betta splendens) and Apistogramma Cichilds. For additional support, gouramis and betta fish sometimes make bubble nests under the leaves, as they float for the first few day.

Betta Fish in an Aquarium with Tan-Tinted Water

Interestingly, Indian almond leaves are known to have very slight antibacterial and antifungal properties. The tannins in plants help protect them from pathogens like bacteria and fungus. Scientists continue to investigate their effectiveness for human medicine. Therefore, many aquarists like to use catappa leaves to heal mild ailments and aid their fish’s immune systems. For example, if you have a betta fish that constantly bites his own tail, adding tannins may help speed up his recovery and prevent fin rot from setting in. Some veterans also recommend adding tannin-rich leaves or alder cones when hatching fish eggs to fight off fungal growth.

As the Indian almond leaf soaks in water, microorganisms begin to consume and break it down. They rapidly reproduce and grow into a layer of biofilm and infusoria. This microfauna makes excellent food for shrimp and fry, and can even be the only food they eat in their early years. If you’re planning on leaving town but don’t know anyone who can feed your shrimp colony, soak several leaves in water for three weeks. They will then become slimy and biofilmy. Then drop them in your aquarium as a long-lasting vacation food while you’re gone.

Blackwater aquarium that mimics a Brazilian forest stream

If you are looking to make a South American or blackwater aquarium that resembles the natural environment of your fish, then use lots and lots of catappa leaves. Darker water allows shiny fish such as neon tetras and cardinal tetras to really shine. Because they are less visible from the tank’s tannins, it makes skittish fish more comfortable. The leaf litter can be used as a hiding place for fry and shy bottom dwellers, such as pygmy corydoras, if you have enough Indian almond leaves.

How to Use Indian Almond Leaves

If your dried leaves are very dirty or dusty, rinse them in water. Aquarium Co-Op catappa leaves are safe enough to drop directly into your fish tank. They usually float for the first 3-7 days, so if it bothers you, weigh them down with a rock or decoration. Also, you can break the leaf in half to just use part of it or crumble it into smaller pieces to speed up the decomposition process.

Ready to use in aquariums

How many catappa leaf should I use for 5-20 gallons? If you are making a blackwater tank, use more leaves and soft woods (like Malaysian driftwood and cholla wood) until you achieve the desired color.

Should I boil Indian almond leaves? We do not boil them because it releases all the tannins and then you don’t get their benefits. However, if you don’t like the way the leaves look, some people like to make a catappa leaf extract by boiling one leaf for every 0.5 gallon (2 liters) of water. (Make sure to use a cheap pot you don’t care about because it may become stained.) After the liquid has cooled down, add a small amount to the tank to achieve the desired color. You can add more extract if you need to.

When is it time to replace catappa leaves? Catappa leaves usually last between one and two months before they completely fall apart. Once you start seeing holes develop in the first leaf, add a second leaf to give it time to start breaking down and releasing tannins.

Caridina cantonensis shrimp chomping on the remains a catappa leaves

Next time you’re thinking of keeping shrimp, breeding soft water fish, or building a blackwater biotope, grab a stack of catappa leaves to get the job done. Aquarium Co-Op leaves can be used right out of the packaging, because they are already cleaned.