Product Description: The Ulin Pod (Eusideroxylon zwageri) is the reproductive seed pod from the Bornean Ironwood Tree. It is tan in color and contrasts against the dark colored substrates of the Botanical Method Aquarium, which are often thick with detritus. We have sourced ours from the dense lowland rainforests just outside Borneo, where these pods belong to one of the most durable trees found in the world. As the pods slowly break down in aquatic environments, they contribute tannins, humic substances, and organic materials, which support microbial life.

In botanical method aquariums Ulin Pods provide a robust surface for biofilms and fungal growths, which in turn feed the microfaunal populations we coin as supplemental nutrition. Their hard woody structures slowly decompose, creating a natural accumulation of detritus that enriches the substrate. They offer foraging areas for shrimp and bottom-dwelling fish like Corydoras and Otocinclus, mimicking the natural accumulation of botanical debris found in tropical vernal pools and streams. When placed at such an angle, they can provide spawning habitats for cave spawning fishes such as parosphromenus, Betta albimarginata, and Betta burdigala.

In bioactive vivariums, these pods serve as an excellent microhabitat for isopods, springtails, and other members of the clean-up crew. Their durable structure holds moisture well, while their complex shape provides shelter and foraging areas, making them ideal for bioactive enclosures. On occasion, these pods are capable of holding water, and we have experienced our Ranitomeya Veradaro Imitators laying eggs and raising tadpoles in them, but these pods have been shown to inconsistently hold water.

Beneath the Leaves on Ulin Seed Pods

Eusideroxylon zwageri, or Bornean Ironwood, is an evergreen canopy tree found in the tropical rainforests of Borneo and Sumatra. Known for its extreme durability, this slow-growing species can live for hundreds of years, with its dense wood naturally resisting decay, insects, and marine borers. The tree produces oblong, woody drupes that serve as seeds, dispersed in the wild by birds and bats.

These trees play a crucial ecological role in their native habitat, forming part of the towering rainforest canopy while contributing to the natural cycle of organic material as their leaves, branches, and fruit fall to the forest floor. The pods themselves are a fascinating piece of this system, acting as a food source and shelter for various organisms before eventually decomposing and enriching the substrate.

Not for Human Consumption. Preparation Required.

Quantities: Available in 6c Ulin Pods. Sizes and shapes range between 1" diameter pods and 5" diameter pods that are 2" to 6" long. This is a natural product, and variation between leaves and botanicals is expected.

Aquarium Botanical Location: Indonesia.

Aquarium Botanical FAQs 

1. Please reference our Shipping and Hassle-Free Return Policy at the bottom of the screen. All Products are packaged inside sustainably sourced and renewable sugar cane fibers allowing them to be fully biodegradable and compostable. Yes, you can bury these bags in your backyard to enrich your soils. 
2. Please refer to our botanical preparation instructions. These Botanicals are grown and harvested in pesticide-free environments and it is recommended to use 2-3 botanical pieces per 5 gallons to start, wait 5-7 days, or for the next water exchange to then add more.
3. Our aquarium and vivarium botanicals, leaves, and seed pods are not for human consumption, ever.
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Commonly Asked Questions:

 

1) Will Botanicals Lower The pH Of My Water?

It entirely depends on your water's chemistry. Soft water will allow the botanicals to lower your pH more than if you have medium or hard water. At Betta Botanicals HQ our tap water is Very Hard, ( 350+ppm) and we do not notice a change in water pH unless using Alder Cones or Macaranga Leaves.

2) What Are The Fluffy White Growth On My Botanicals?

White growths are the colonization of biofilms and fungi. We call this the 'goo phase' and it is totally natural. Botanicals are fuel for the ecosystem and the populations of bacteria and fungi will naturally rise and fall. 

3) I Don't Keep Bettas. Will These Botanicals Be Okay For My Critters?

100% yes. Our botanicals are for aquariums, terrariums, vivariums, and all natural enclosures wishing to recreate a more natural environment.

4) I Have Goldfish and Axolotls, What Botanicals Should I Avoid?

We DO NOT recommend using botanicals that these fish can ingest. Botanicals like casuarina cones, small alder cones, and live oak are not suited for these animals. Large aquarium leaves like Indian almond, loquat, and jackfruit leaf litter are preferred. 

5) When Should I Replace My Aquarium Leaves?

We recommend letting aquarium leaves and seed pods entirely break down into beneficial detritus. You can absolutely remove them after they don’t release tannins anymore, you just won't get all potential benefits of leaving them in the ecosystem.