Wisdom about wood...Patience, persistence...and aesthetics.

If you're like me, you are virtually fearless about dumping all sorts of natural materials into your aquariums...It's kind of what you do. Sure, there is a learning curve in regards to how much you can "get away with", but the potential for breakthrough benefits for your fishes is too great to overlook for many of us.

Someone asked me if we are going to start offering (insert stupidly-named wood type here). And of course, I had to think about this for  just a bit. 

It seems to me that, on any given day, such-and-such a wood type is the "IT" variety, and everyone wants it. Some guy does a tank with this scraggly shit emerging from the water, posts a few sexy pics on his Insta feed, and the next thing you know...trend.

As someone who offers natural aquascaping materials for use in specialized aquariums, I long ago realized that I needed to stop chasing every hot type of wood that shows up on the market. I have found some types which have proven to be great to use in our natural-style aquariums. I am generally clueless on "what's hot" in the aquascaping wood world.

We'll continue to offer types of wood that we enjoy using in our own 'scapes. Some will just happen to be ones that are popular and relatively common- or even "trendy" at the moment. Some will be types which fell out of favor with the mainstream 'scaping world. Some will be obscure, niche-specific stuff.

The majority, however, will simply be stuff that works.

That answers that., I hope?

Of course, that means I'm really the last guy who should be discussing what wood to use in your aquascapes. Rather, it will be a discussion on what happens at that magical moment when we place wood in water...


First off, let's think about where our wood comes from.. It doesn't take much to figure out that the most important thing is that the wood must be…well, DRY! It can’t be “live”, or have any greenwood or sap present, as these may have toxic affects on fishes when submerged. Sap can be toxic, even when dry, so if you see a piece of wood that’s oozing some sap- it might be a good idea to take a pass. For the sake of this discussion, let's just assume that you're working with wood that's been properly collected and is suitable for aquarium use.

When you first submerge wood, a lot of the dirt from the atmosphere and surrounding environment comes off, along with tannins, lignin, and all sorts of other stuff from the exterior surfaces and all of those nooks and crannies that we love so much. And the stuff typically floats, much to our chagrin, right?

And of course, there are the tannins. Now, I don't know about you, but I'm always amused (it's not that hard, actually) by the frantic posts on aquarium forums from hobbyists that their water is turning brown after adding a piece of driftwood. I mean- what's the big deal?

Oh, yeah, not everyone likes it...I forgot. 😂

The reality, as you probably have surmised, is that driftwood will continue to leach tannins pretty much for as long as it's submerged. As a "tinter", I see this as a great advantage in helping establish and maintain the blackwater look, and to impart the humic substances that are known to have health benefits for fishes.

Some wood types, like Mopani, tend to release more tannins than others over long periods of time. Other types, like "Spider Wood", will release their tannins relatively quickly, in a big burst. Some, such as mangrove wood, seem to be really "dirty", and release a lot of materials over long periods of time.

And it's a unique aesthetic, too, as we rant on and on about here!

What I'm more concerned about are the impurities- the trapped dirt and such contained within the wood. As you probably know, that's also why I'm a staunch advocate of the overly conservative boil and soak approach to the preparation of botanicals as well. A lot of material gets bound up in the dermal layer of the tree where the wood comes from. Atmospheric dust, pollutants, bird droppings, insects, etc.  None of this is stuff you want in your tank, right?

The bulk of the dry mass of the xylem (the "network" within the tree which transports water and soluble mineral nutrients from the roots throughout the plant, and comprises what we know as "wood.") is cellulose, a polysaccharide, and most of the remainder is lignin,  which is a sort of complex polymer. 

Why the botany lesson?

Well, because when you have some idea of what you're putting into your tank, you'll better understand why it behaves the way it does when submerged! In a given piece of driftwood, there is going to be some material bound up in these structures, and it will be released (gradually or otherwise) into the water that surrounds it, with a big "burst" happening on initial submersion. This is why, during the first couple of weeks after you submerge wood, that the water often becomes dark and even cloudy.

There is a lot of "stuff" in there!

It's far better, in my opinion, to take the time to start the "curing" process in a separate container apart from the display aquarium. This is not rocket science, nor some wisdom only the enlightened aquarists attain. We all know this, right?

It's common sense, and a practice we all need to simply view as necessary with terrestrial materials like wood and botanicals. You may love the tannins as much as I do, but I'm confident that your tank could do without those polyscaccharides and other impurities from the outer layers of the wood. The potential affects on water quality are significant!

It's pretty plain to see that at least part of the reason we see a burst of new algae growth and biofilm in wood recently added to an aquarium is that there is so much stuff bound up in it. Algal and fungal sports can literally "bloom" during the initial period after submersion, and this alone is great reason to take the long, slow approach to wood prep.

In fact, geek that I am, over the years I've long made it personal practice to submerge wood which I intend to use in my tank a couple of months before I set up my tank. This will enable a good percentage of the bound-up contaminants and unwanted organic materials to be released before the wood ever graces your aquascape! And it goes the wood a chance to saturate and sink, too!


What about boiling?

Well, sure, boiling can hasten the process somewhat. But here's the deal-most of us don't have a kettle, pot, or other large enough container in which to boil a big old piece of wood, so the long-term "pre-soak" is the optimal approach. 

And let's face it, even with preparation, when you combine water, light, and organics, you're likely to get some fungus, biofilms, and even algae- for some period of time. Some fungal growth and biofilms are to be expected in the earliest days of "submersion. These tenacious life forms will exploit available nutrients and conditions that are appropriate for their survival. Just like with our botanicals, it's a normal occurrence.

We may not like the way it looks in our tanks. I totally get that.

Now, I remember deliberately NOT pre-soaking the wood in my office tank (I love torturing myself, apparently) just to see how nasty this could be. (oh, the things I do for you in the interest of sharing knowledge!)

The result? It literally took about 4-5 months before the wood stopped producing biofilm and attracting hair algae in really large quantities.

That was freaking punishing. Well, I found it kind of cool, but pretty much everyone who saw the tank during this period thought otherwise...😫

Eventually, the familiar "patina" of harder algae came to prominence.  And minor biofilm on the softer parts of the wood will still pop up on occasion...Just like it does in nature. It's normal. It's not dangerous.

It's okay.

And of course, along the way, you can incorporate some "biological helpers", like algal and detritivorous-consuming fishes and even snails (yikes!) to help out. Of course, many, many fishes will "peck" at biofilms and other growth on wood and botanicals as a part of their daily "foraging" activities.

And of course, good old-fashioned aquarium husbandry and stepped-up maintenance practices never hurt, either!


And having a good, soft-bristled toothbrush on hand can help with the "day-to-day" upkeep, if needed. Likely, the stuff will continue to return until the "fuel" which caused their appearance and growth in the first place diminishes.

Obviously, happy endings typically will happen with aquarium wood, given the passage of time and perhaps a bit of assistance from the fish geek, but it's important to understand WHY the algae and biofilms appear on wood, and how to react when they happen.

Like so many things in a truly "natural" aquarium, they may not meet our aesthetic standards, but if we have a greater understanding of just what they are, why they appear, and how to address them (or not..), we can make that "mental shift" that you hear me ranting about so often on these pages.

Embracing a new paradigm of what a "natural" aquarium really is.

One that doesn't cause us to rush off, headless, screaming into the night (or onto Facebook) when some algae or biofilm appears! Goes with the territory. Embracing Nature in all of her glory is what we're all about. 

Expectations. Education. Patience.

All "core skills" which we as aquarists need to acquire to bolster our success, understanding and perseverance as we push the boundaries of aquarium keeping.

Stay diligent. Stay patient. Stay curious. Stay bold. Stay focused...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

Scott Fellman
Scott Fellman


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