We can't "leaf" this topic alone....

[Tannin Aquatics]

So we talk a ton about how cool, useful, and desirable it is to have leaf litter in your aquarium, don't we?

Well, I think our enthusiasm stems from the fact that when properly and aesthetically employed, leaf litter adds a new dimension to a biotope-inspired aquarium, and adds a functionality that cannot be denied. Blackwater rivers and streams are characterized by large quantities of leaf litter and decaying botanicals on the bottom, with typically clear (but tinted) water. As discussed many times in this column, leaf litter is used as shelter, spawning ground, feeding area, and in some instances, as supplemental food itself. This is a highly productive habitat in nature that also just happens to look really cool in our aquariums, performing exactly the same function!

In wild habitats, there have been many instances where researchers have counted literally hundreds of fishes per square foot inhabiting the matrix of botanical materials on the bottom of stream beds, which consists primarily of leaf litter.  As dead leaves are broken down by bacterial and fungal action, they develop biofilms and associated populations of microorganisms ("infusoria", etc.) that are an ideal food source for larval fishes. When you take into account that blackwater environments typically have relatively small populations of planktonic organisms that fish can consume, it makes sense that the productive leaf litter zones are so attractive to fishes!

Obviously, as leaves break down, the look of your aquascape will "evolve", literally "morphing" into a different scene over time. Consider leaf litter a "transitional" or "consumable" product that needs replacing over time. One of the most common questions we get is how often you need to replace your leaves. Here's my take on the subject: 

You don't have to remove the decomposing leaf litter, unless you simply don't like the look. Part of the "charm", if you will, of leaf litter is that it is a surprisingly dynamic environment to watch. However, there are situations where leaving the material in could be detrimental: If it's creating unsanitary conditions, such as trapping excessive amounts of uneaten food, fish waste, etc,degrading water quality- then you'd want to a)review your husbandry practices and b)consider siphoning some of the material out. For most of us, however, I'd say to just leave the stuff in, and add new leaves as needed to maintain the "density" and aesthetic you want. 

Preparation is another important part of incorporating leaf litter in your system. There are differing viewpoints on whether or not you should boil or steep the leaves. I definitely would not boil the leaves, because I feel it will remove much of the beneficial tannins and humic substances from the leaves right away. However, I take a very conservative approach in my recommendation to customers and fellow hobbyists: I say that it's never a bad idea to rinse, steep, and soak leaves before placing in your tank.

My main concern about leaves you collect yourself is contaminants, pesticides, etc., so anything you can do to eliminate them is important. They should be dried, of course, before you incorporate them. Don't skip the prep! The leaves I sell are pesticide free and free of major pollutants, yet still should be rinsed at the very least before use. I like the idea of steeping leaves in boiling water for 10-20 minutes, which helps soften them up a bit and "sterilizes" them to some extent, without "cracking off" all of the beneficial tannins bound up in their tissues.

My personal practice is much more liberal: I'll give the leaves a good rinse and typically let them soak a day or two to waterlog them before adding them into my aquariums. Really, the only reason I don't add leaves to my tanks straight away after rinsing is that, with the possible exception of "nano-sized" Catappa leaves, most of them don't sink immmediately!

So, how long do your leaves last? Well, it depends on so many factors, ranging from water chemistry to how "rough" your fishes are with them! Typically, a Catappa leaf will last a month or so before it really starts to break down. Guava, on the other hand, tends to last a much longer time in my personal experience, sometimes 2-3 months or more. Loquat lasts even longer in many cases; I've had some with me for 6 months or more! Others, like oak, beech, Magnolia, etc. are variable.

How dark will your water become as a result of adding leaves? Again, no real one answer- it's a function of many factors combined. In general, I'd suggest starting slowly, particularly if you have very soft water, which can result in significant pH dips rather rapidly when you add a large quantity of leaves at once. An important note: Leaves will not soften hard water. This is a common misnomer. Remember, just because they are staining the water with tannins doesn't necessarily mean that they are softening, or even acidifying, the water to any measurable extent.

They will possibly impact the pH in harder water, but not nearly to the extent that they will in soft water, which is devoid of most buffering capacity/mineral content. It might be argued that a "hard water/blackwater-aesthetic" style system is easier to manage (from a chemical standpoint, at least) than a soft water blackwater aquarium. I'd go so far as to say that a soft water blackwater aquarium with leaf litter and botanicals is on par with a reef aquarium, in terms of the need to manage and care for it. No more difficult than that- it just requires you to be on top of things.

The important takeaway from this brief and highly cursory discussion on leaves is that you should consider them as both a functional and aesthetic component of a well-managed biotope-inspired aquarium for many fishes. The look, the characteristics, and the utility of leaf litter makes it well-worth considering for anyone who is contemplating keeping Characins, Dwarf Cichlids, Catfishes, Barbs, Anabantoids, and many other species of fishes which hail from "blackwater" environments. And of course, shrimp as well!

I hope you'll learn not to be afraid of the dark (water), and perhaps play around with some leaves in one of your aquariums!

Stay adventurous. Stay focused. Stay engaged.

Stay Wet.

Scott Fellman

Tannin Aquatics

 

 

 

 

 

[Vpier]

I know this is off the topic but what I like about the market you are developing is the fact that all of the materials you sell don't require someone to destroy, kill or damage the surroundings to obtain the product. Nature grows it on its own and releases it to the ground. For a lot of people in the tropics its a way to make a little money on something that would just rot away and they dont need to harm the environment which is a rarity in poor tropical regions.

[Tannin Aquatics]

1 hour ago, Vpier said:

I know this off the topic but what I like about the market you are developing is the fact that all of the materials you sell don't require someone to destroy, kill or damage the surroundings to obtain the product. Nature grows it on its own and releases it to the ground. For a lot of people in the tropics its a way to make a little money on something that would just rot away and they dont need to harm the environment which is a rarity in poor tropical regions.

True, for the most part. I think that there is more-and will be more- that I can do-to help in this arena...Sustainability and support of indigenous communities is something that I know I need to improve upon with my offerings and business, and I think every aquarist can make a difference!

 

-Scott

[Purplepanda]

Enjoying this leafy gossip, thanks ! Just one little observation and with growing all in my yard and then regularly using catappa, guava, loquat and mulberry in my shrimp tanks, guava definitely seem to take the longest to break down not loquat, while this takes about the same time as catappa. Mulberry as you suggest is the quickest and relished immediately by the shrimp with hardly time to generate biofilm. I'm also adding alder and leucodendron cones into the mix and a variety of woods including cholla.. 

[Tannin Aquatics]

1 hour ago, Purplepanda said:

Enjoying this leafy gossip, thanks ! Just one little observation and with growing all in my yard and then regularly using catappa, guava, loquat and mulberry in my shrimp tanks, guava definitely seem to take the longest to break down not loquat, while this takes about the same time as catappa. Mulberry as you suggest is the quickest and relished immediately by the shrimp with hardly time to generate biofilm. I'm also adding alder and leucodendron cones into the mix and a variety of woods including cholla.. 

Great information!-thanks for sharing! I think it's interesting that the Loquat breaks down more quickly for you than for me...I'm sure it has to do with a myriad of factors, including my water chemistry, etc. I recently started offering "indian Alder Cones" (Casaurina), and they seem to have a bit more "potency and last a tad longer than the European/North American Alder Cones that we're used to..again, in my case, lol.

[Purplepanda]

Yes not sure if there are different species of loquat but mine break down completely within say two weeks while the quava go on for many months..but again perhaps we are not comparing the same exact plants.    As for water chemistry these are all in shrimp tanks so most have  mineralized RO water with ADA substrate.

 

Love your earthy quality pics Scott, keep them coming !  

[Tannin Aquatics]

Just now, Purplepanda said:

Yes not sure if there are different species of loquat but mine break down completely within say two weeks while the quava go on for many months..but again perhaps we are not comparing the same exact plants.    As for water chemistry these are all in shrimp tanks so most are mineralized RO water with ADA the substrate.

Yeah, so many variables..Also, perhaps the "age" of the leaves at the time of use is also a factor...