"Wood" you? Well, yes, I will!

We receive a fair number of questions here at Tannin, about our products, their usage, and impact on the aquariums they are to be used in. We love this kind of stuff, because it tells us that hobbyists are engaged and interested in what we offer. When you're concerned at how a botanical is going to affect your ____ gallon aquarium with (insert favorite fish here) in it, means that you're engaged and interested...and we love that!

One of the questions we receive quite often is about the aquatic wood that we offer, and how best to prepare it; what the affect is on water, etc. Let's take a quick look at the most popular wood types that we offer, and a few comments on their preparation and aquarium use.

First off, we have the major star of our wood show, Manzanita. We've written about Manzanita's origins before, so I won't bore you with that. However, I will give you a little more on its preparation and use in the aquarium. First off, I'm not exactly certain why, but Manzanita takes a pretty "predictable" amount of time to waterlog and sink..In my experience, it's almost always like 4 days at the most for pieces up to about 20" in length. It's almost uncanny how accurate this is! Sure, some will sink in a day, but most, for me- are 4 days and they're sunk!

Manzanita will not discolor the water all that much, in my experience. A lot of people give it a good rinse and just "plunk it down" into their tank, perhaps securing it so it won't float up, and call it a day. I've done that before, but I prefer to pre-soak it a bit before immersing it in the aquarium. Why? Well, like anything terrestrial and dried out (that's a good chunk of what we offer, huh?), you need to give wood pieces a decent rinse, to rid their surfaces and crevices of debris, dust, etc. The soak helps them: a) continue to rid themselves of any surface dirt, b) allow any sugars remaining in the dermal layer of the wood to leach out a bit, and c) really let the water penetrate into the deeper layers of the wood structure, assuring that it will stay down.

For some reason, and I'm not sure what it is- Manzanita tends to "recruit" a white, cottony fungus on it surface sometimes during the first few weeks. The first thing you need to know is that this stuff is harmless. It just looks like &*&%$. It typically will go away on its own with minimal intervention on your part, but you could always give it a good scrub with a soft-bristle brush (like an old toothbrush), and a rinse in freshwater. Alternatively, you could employ shrimp, Otocinculus catfish, or even your trusty Pleco to help rid the surfaces of this ugly-looking stuff. Of course, you can just wait it out and let it run its course, but I cannot blame you for not wanting to wait and watch your nice piece of wood emerged in "cotton balls" for a few weeks. This wood darkens a bit over time, taking on a dramatic, beautiful "patina" which is, in our opinion, undeniably attractive.

The next popular wood we work with is "Mopani" wood, from Africa. We've also written loads on this beautiful wood in the past, right here in our blog. This is a heavy, beautiful wood which looks amazing. Unlike the more "mild mannered" Manzanita, Mopani apparently has no qualms about releasing a lot of tannins during it's "curing" process, and beyond. This stuff packs a serious wallop, which I personally love (I know you're shocked by that). I've seen a small (roughly 10" long) piece stain the water thoroughly and beautifully brown in a 20 gallon aquarium in just a couple of days, even after a two day soak in fresh water! 

Confession: I love seeing this posts in various aquarium forums where hobbyists freak out about this, and put out desperate requests for help: "My new driftwood is turning my water brown?  What do I do?" Obviously, these are not Tannin Aquatics customers, who understand what's going down, and I've always wanted to chime in and say something like, "Sweet! Don't do anything! Your tank looks awesome!" Other than being a personally satisfying venture, taunting an already traumatized hobbyist on a message board would not endear myself of my company to the public, so I refrain. Of course, the reality is that a good part of the fish keeping world doesn't like golden brown water (or, more precisely, doesn't understand), so we'll have to forgive these heathens while we gently try to change their mindset..I digress...

So, to get rid of the tannin coloration is relatively straightforward, as we've discussed before. Just do a few small water changes and employ some activated carbon, or my personal fave chemical filtration media, Seachem Purigen, and you'll see your water clear up within a few days in most cases. To avoid as much discoloration as possible, you really want to soak the wood for a couple of weeks, and change the water in the sack container every few days. Patience is required with this wood, but it's well worth the effort, and this wood offers few other caveats for its use. That being said, Mopani will occasionally get that surface fungus that we've talked about above, and you can resolve it the exact same way as for Manzanita. 

The final member of our popular wood "triad" is "Spider Wood." This stuff is, as we say here in L.A. "gnarly!" and amazingly useful for 'escaping! It's a pretty light wood and typically will float for a while before eventually settling down. Some pieces sink quickly. Others require a lot of patience on your part. We had this grandiose idea that we'd sell it "ready to use" and try to pre-soak the wood here before we offer it for sale, but the reality is that, once it dries out again, it...floats. Hey, we tried. So purchase this would with the mindset that you'll have to do some soaking. 

Oh, and it leaches some tannins. Yup. Like all woods, Spider wood tends to leach out a fair amount of tannin for a few weeks at least. Again, the key to reducing the amount of tannins being released into your tank is essentially the same as what it takes to sink it: patience, and the passage of time. A few weeks weighted down in a container of water, along with regular changes of the water in the container, and you'll be good.

The good news is that Xylophagic (wood eating) loricariids (your Plecos!) will use this stuff like a "chew toy", and love to rasp at it over time, slightly "modifying" your wood's appearance as it ages. This is a pretty cool phenomenon, and a lot of fun to watch!

So there you have the briefest of rundowns on dealing with our most popular aquascaping wood. As you can tell, they all have some similar "habits", such as being bouyant, leaching tannins, and recruiting biofilms/fungus.

The patient hobbyist understands this, and plays a "long game", taking the time to properly prepare the wood for aquarium use, and embracing and understanding how the wood reacts with its aqueous environment.

No one will ever debate the attractiveness of driftwood in the aquarium (well, some might, but they'll be roundly and deservedly thumped by fellow aquarists!), and the extra understanding, appreciation, and time it takes to get to know what you're dealing with when employing it is well worth the beautiful aesthetic results that it can bring to your aquascape!

Until next time...

Stay creative. Stay patient.

And Stay Wet.

Scott Fellman

Tannin Aquatics

Scott Fellman
Scott Fellman


5 Responses

Stamford Soo
Stamford Soo

November 09, 2023

Please advise how to get of Agila woods tannins in my 100US gallons fish tanks,. I placed Seachem Purigen 250ml in filter cylinder for 1 month, the water still look brownish. I love to see crystal clear water plants and fishes.
Appreciate if you could furnish some advise
Thanks, Stamford Soo

Scott Fellman
Scott Fellman

February 15, 2021

Hi Wendy,

Yes, we think having the tannins and humic substances in the water from wood is a good thing! However, think about this for a second. When you boil wood, it’s to saturate it and sink it, and also to “crack off” some of the bound-up dirt and/or pollutants found in the surface layers of the wood (same goes for botanicals). So, my thinking is this: Why would you want to add what is essentially a concentrated “stew” of these things- the very materials you are really trying to eliminate, right? Yes, there are tannins, but your wood will produce far more over it’s “operational lifetime” submerged in your tank than you will lose by dumping the “tea” in the garden. Well, that’s my two cents worth!

Thanks for stopping by! -Scott

Wendy Manzo
Wendy Manzo

February 15, 2021

I’m confused! Tannins are good but all the google searches bring up ‘how to remove’ tannin from your tank. Driftwood is good but it carries bugs so best boil it first. So I’ve soaked petrified tree roots (good wood, didn’t float so its quite petrified) for a couple of weeks and still I was wary about bugs, so I boiled them for a few hours. I now have a pot of ‘tannin tea’. Some say put it in the tank, some say it is useless because it has been boiled. I’m confused. Are tannins worth keeping ???

Scott Fellman
Scott Fellman

December 25, 2019

Thanks for the kind words. Fun for us to share our love of this stuff, too!

Great question. As a long time acrylic aquarium user, I’ e noticed over the very long term (a couple of years), that you might experience some slight discoloration of acrylic..Of course, there are numerous factors- ranging from the pH of your water, to the specific “tinting” materials used…I think it’s something you probably needn’t worry about too much, but it is a consideration!




December 24, 2019

What An AWESOME website. It’s set up like the aquariums and products featured on here—minimalist and classic. If you want a ‘classy’ aquarium, look NO further. I personally LOVE the look tannins add to my glass tank. I do, however, have a question for all of us who also have expensive acrylic aquariums. Will the tannins stain the acrylic permanently? I will still be purchasing from you but I just want to know if I need to soak and boil for even more time if I’m putting things in my acrylic. My glass I love tea colored! And my fish get along better. It’s true!

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