Revisiting the art and science of botanical preparation.

Over the years, we've developed a lot of "technique" for doing "stuff" with our blackwater/botanical-style aquariums. One of the most fundamental tasks associated with our tanks is the preparation of botanicals for aquarium use. It's as much an "art" as it is a "science"- in fact, it's not really a "science."

The idea is to get your dried botanical materials into a condition where they are both reasonably clean, and with their tissues saturated sufficiently to cause them to sink. This usually involves some simple, yet possibly time-consuming tasks, as we've all come to know.

There are basically three ways to prepare most botanicals for use in the aquarium:

1) Boil them/steep them in boiling water

2) An overnight (or longer) soak in room temperature water

3)  A combination of both.

Always rinse any of our aquatic botanicals in clean fresh water before use, even after boiling or soaking. This will rinse away any loose dirt or organic material that has adhered to their surface tissues. Just sort of a "best practice", IMHO.


For the vast majority of botanicals, you'll need to boil them in a clean pot for at least 30-40 minutes; many stubborn ones (ie' really buoyant botanicals) may take more than an hour of continuous boiling!

The boiling process not only saturates the tissues of many botanicals, it breaks them down a bit, and helps release any surface dirt that might be remaining (like dust, pollen, spider webs, etc.). The boiling serves the dual purpose of helping release pollutants and getting them to absorb water to sink. (No one likes a floating pod)

Materials like leaves don't necessarily need to be boiled; you might elect to simply "steep" them in boiling water for a period of time (like 20 minutes or more) to help soften them and get them to sink. This process works fine for leaves like Catappa, Loquat, and Guava- a bit less so for the more "durable leaves, like Magnolia, Mangrove, and Jackfruit.

During the boiling/steeping process, many of you have remarked how wonderful the resulting "tea" smells, and we can't argue with that! It sort of creates a total sensory experience! A lot of you ask if you can use the water that the botanicals were boiled in as a sort of homemade "blackwater tonic." Now, on the surface, it seems like a pretty good idea. I mean, you're adding this botanical stuff into your aquarium, so what's the harm in adding the water they were boiled in as well? There's all those beautiful tannins they released...

...and the surface dirt, bound-up organics, sugars, dust, etc. as well- sort of concentrated. Would you really want to add THAT stuff into your tank? I know I wouldn't.  The closest analogy I can think of is the idea of adding nasty stuff that your protein skimmer removes from the water in your reef tank back into the tank. Once you see and smell that crap, you wouldn't even consider it! 

Now, our little "tea" isn't nearly as nasty as protein skimmer effluent, but it is still la sort of concentrated "cocktail" of stuff that I'm hesitant to add to the cozy confines of my aquarium.  It waters my garden.



That being said, plenty of you DO add this stuff without incident.

The oft-cited reason being that you, "don't want to waste all of those wonderful tannins!" Trust me, there are more when're that came from- don't worry. Even well-aged and prepared botanicals will, in my experience, continue to leach water-tinting tannins for extended periods of time.

However, it's your call here, of course...

Following the boil, you can give the botanicals a quick rinse, and either add them to your aquarium, or (and I like this idea better), place them in some clean, room temperature water overnight, or longer. If you want, you could even throw in some chemical filtration media (activated carbon, Purigen, etc.) passively to adsorb any remaining pollutants which might be released following the boil. And of course, soaking the botanicals also serves to fully saturate them and make sure that they stay down!


Can you avoid the boiling process altogether?

Sure, it's possible...conditionally.

With some botanicals, such as leaves, it might take a few days, but soaking them in room temperature freshwater can help saturate their tissues and get them to stay down, while releasing some of the aforementioned pollutants bound up in their surface tissues.

With the more "durable" botanicals, like "Jungle Pods", "Savu Pods", "Ceu Fruta", etc.- it's pretty challenging, because they have that hard exterior which makes saturation of the tissues to the point where they'll sink very difficult and time-consuming. Boiling is a better choice, because it breaks down some of the surface tissues, better preparing them to absorb water.

And of course, you can just place them in the tank and let them soak there and performing a water exchange before continuing with the "startup process." "In situ" preparation works fine, in my experience when you executed it in this manner.





Like anything we do in the aquarium world, botanicals have good and bad stuff associated with their preparation and use. 

An annoying thing about botanicals is that there are many that simply won't sink, even after an hour or more of boiling. You can continue to leave them "steeping" in water for as long as it takes to "get 'em down", or you could put them in a mesh filter bag and keep them in your canister or outside power filter to continuously pass water over them. I even played around with a coffee "French Press" technique that worked..All of these tricks can help!

And of course, there are always caveats...


The simple truth about using botanicals is that you're adding natural terrestrial materials that, when acted upon by bacteria, break down in your aquarium, increasing the bioload of the system. We've said it thousands of times over the past few years, and we'll say it again here- you need to add botanical materials to your aquarium slowly, over a period of days or weeks.  You have to be careful. You have to observe, test, and adjust.

Think about it: It's not really a revelation. Adding large quantities of ANYTHING in a short period of time into your established aquarium could cause some issues. And it starts with our friends, the bacteria, and the biofilms which they create.

Biofilms form when bacteria adhere to surfaces in some form of watery environment and begin to excrete a slimy, gluelike substance, consisting of sugars and other substances, that can stick to all kinds of materials, such as- well- in our case, botanicals.

Biofilms are THE foundation of life in most streams and rivers. Other major components of biofilms are bacteria, fungi, archaea, and protozoa. They are an important part of the aquatic environment- even a food source for many organisms.

However, in an extremely overcrowded aquarium (or a very small one) with marginal husbandry and filtration, with a huge amount of biofilm (relative to tank volume) caused by an equally huge influx of freshly-added botanicals, there is always the possibility excessive respiration by biofilm bacteria could lower the water’s dissolved oxygen and increase CO2, asphyxiating your animals and the important aerobic nitrifying bacteria.


YIKES! That's sort of a doom and gloom scenario, huh?

Well, yeah- it can be if you're not careful.

Which is why we've continuously emphasize going slow and steady when adding botanicals to your aquarium. However, use of botanicals need not be scary, problematic- or even mystifying. You just need to deploy observation, patience, and a healthy dose of common sense.

No more exotic or complicated than the effort extended to maintain any sort of aquarium, really.

It's a growing worldwide practice, a genuine "movement" within the aquarium hobby, with hobbyists creating amazing, stable, functional aquariums with these unique materials.

 So the real "secrets" of the botanical preparation process? Prepare carefully. Add slowly. Observe, test, and tweak as necessary. 

Simple, if you make it that way. 

Keep it simple. Be responsible and vigilant. And...enjoy the process.

Stay excited. Stay involved. Stay intrigued...

And Stay Wet.


Scott Fellman

Tannin Aquatics 







Scott Fellman
Scott Fellman


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