Be Mindful of the Organic Material Exchanged between Terrestrial and Aquatic Environments
Aquarium botanicals allow the aquarist to better emulate a natural aquatic environment using dried plant materials as décor in the aquarium. In nature, vegetated shorelines shed branches, leaves, seedpods, and other debris into nearby water bodies, to settle on the benthic floor. These diverse organic materials can be used in the aquarium and are referred to as botanicals. Including botanicals in the freshwater aquarium helps to acidify and soften water conditions, by providing a source of tannic, fluvic, and humic acids. Botanicals also come in various shapes that provide a dynamic habitat for aquarium inhabitants and they encourage biofilm growth that can support raising more challenging species.
Dried Leaves
Leaf litter is one of the most natural-looking additions to the soft water aquarium habitat. A few layers of leaves on the aquarium bottom provide an interactive environment for fish like Apistogramma cichlids, Corydoras catfish, killifish, and shrimp! Also, Betta fish benefit from dry leaves left floating on the surface long enough to build a bubble nest. Dried leaves in the aquarium can help to enhance the visual depth perspective when small-sized leaves are matched with small-scale aquascape scenes, additionally, the presence of leaves inherently expresses seasonality and the element of time. The aquarist may choose leaves based on shape, size, tannin concentration, longevity, preparation, and so forth.
Leaves can be purchased as organic and dried, or the aquarist can collect, wash, and dry local plant leaves that have been identified as safe. Additional aquarium-safe leaves include some fruit trees like Apple (Malus pumila), Pear (Pyrus spp.), Cherry (Prunus cerasus), and Plum (Prunus domestica); even Dandelion (Taraxacum officinale), and Bamboo (Poaceae spp.), as well as other deciduous Alder (Alnus glutinosa), Ash (Fraxinus spp.), Maple (Acer spp.) and Beech (Fagus spp.) tree leaves.
Generally, add 1-3 leaves per 10 gallons, add biweekly to accumulate leaf litter, and replace as necessary. Pieces of leaves can also be used in filter bags for convenient replacement.
Note: Adding too many leaves at one time can increase the biological oxygen demand in the aquarium and may put the inhabitants at risk. Therefore, caution should be used when adding or accumulating large quantities of organic matter in an aquarium system.
A few popular leaves are described below:
Indian Almond Leaves (Catappa or Ketapang)
Terminalia catappa
Origin: India, Singapore, Sri Lanka, China (Southeast Asia, Africa, Australia)
Leaf Size: 5-40 cm long, 3-20 cm wide
Tannin Level: High
The Indian Almond Leaf (IAL) is known for having a very high concentration of beneficial tannins, apparent by the darker brown and red pigmentation when dry. Additionally, the leaf petiole (stem) contains a large concentration of tannin, making the entire leaf valuable. The anti-bacterial & anti-fungal tannins condition the water for soft water fish for breeding and protect eggs after spawning. The surface biofilm accumulation and decomposition of the leaf help to supplement the diets of grazing fish and invertebrates.
Guava Leaves
Psidium guajava
Origin: Central and South America (also grown in India, Sri Lanka, Malaysia)
Leaf Size: up to 20 cm long, 7 cm wide
Tannin Level: Medium
The Guava Leaf is known for having a much lower tannin concentration, resulting in lightly tinted water. The leaf is smaller in size, the colour can range from light green to brown, and parallel venation makes the guava leaf attractive in the aquarium. Additionally, the antibiotic properties of the leaf (shown effective against Luminous bacteria and Bacteria Vibrio) have made the guava leaf practical when keeping sensitive fish and invertebrates, including Caridina and Neocaridina shrimp. Leaf decomposition provides fibre and biofilm that supplement the diets of sensitive fish and invertebrates.
Banana Leaves
Musa acuminate (family Musaceae)
Origin: Southeast Asia (tropical regions)
Leaf Size: up to 200 cm long, 30 cm wide
Tannin Level: Low
The Banana Leaf produces a light brown tint that allows the aquarist to maintain water clarity in the aquarium. The leaf surface is known to accumulate biofilm which is an acceptable food for plecos, sensitive fish, and invertebrates, like Neocaridina and Caridina shrimp. The banana leaf can grow 2 metres in length, so it is cut into strips or squares for use in the aquarium. Banana leaf strips decompose faster than other leaves.
Other Leaves: Oak, Teak, and Jackfruit Leaves
Oak
Quercus rubra (red), Quercus alba (white)
Origin: North America (Canada, United States)
Leaf Size: up to 20 cm long, 15 cm wide (red); up to 15 cm long, 10 cm wide (white)
Tannin Level: Medium (red), Low (white)
Red or White Oak leaves may be locally available or featured on a neighbour's front yard, for collection in the fall. The lobed leaves contribute a contrasting leaf shape in the naturalized aquarium. Red Oak leaves can be easily identified as having pointed leaf lobes, when compared to the smaller White Oak leaves with rounded leaf lobes. The oak tree is exceptionally useful, given that oak branches, bark, and acorn caps are also suitable aquarium botanicals.
Teak
Tectona grandis
Origin: Southeast Asia (Sri Lanka, Malaysia, Thailand, Indonesia)
Leaf Size: up to 10 - 45 cm long, 5-20 cm wide
Tannin Level: Medium
Teak leaves are regarded as a substitute for the Indian Almond Leaf. However, the teak leaf tannin concentration is not as strong. The teak leaf is shaped wider at the end and has a soft textured underside. These leaves can grow very large.
Jackfruit
Artocarpus heterophyllus
Origin: India
Leaf Size: up to 15cm long, 10 cm wide
Tannin Level: Medium
Jackfruit or Katahal leaves have gained recent online popularity. They have a thicker leaf that lasts longer underwater. The oval leaf has a moderate tannin concentration. The smaller-sized leaves are ideal for nano aquariums.
Nutritional Leaves: Mulberry, Nettle, and Soybean Leaves
Mulberry, Stinging Nettle, and Soybean leaves provide a varied food and vitamin supplement readily accepted by shrimp, snails, catfish, and other grazers. These leaves are harvested when green and sundried or dehydrated to preserve a high concentration of vitamins, minerals, and other beneficial bioactive compounds (including fat, protein, carotenoids, tannins, antioxidants, and so forth). To ensure your aquarium inhabitants have access to these nutrients, the leaves can be added raw following dehydration, or after blanching (soaking) for 1 or 2 minutes in boiling water. Feed 1 - 2 leaves per 10 gallons once or twice per week.
Mulberry
Morus alba (White Mulberry); Morus rubra (Red Mulberry)
Origin: China, India
Leaf Size: up to 15cm long, 10cm wide
Tannin Level: Low
Nutrition: Vitamin B-6, Vitamin C, Iron, Potassium, Carbohydrate
Stinging Nettle
Urtica dioica
Origin: India
Leaf Size: up to 12cm long, 8cm wide
Tannin Level: Low
Nutrition: Omega-3, Carotenoids, Calcium, Iron
Soybean
Glycine max
Origin: East Asia
Leaf Size: up to 15cm long, 10cm wide
Tannin Level: Low
Nutrition: Calcium, Nitrogen, Potassium
Take Away
Now that you're familiar with the benefits, these tannin- and nutrient-rich leaves might just give your aquarium environment the edge when breeding a challenging species, or when inspired to aquascape based on a geographical region.
Please comment below!
Well written and informative. Great article!