For the love of rock...

Like many of you, I enjoy playing around with aquascapes. I'm interested in creating all sorts of aesthetics which tie in with the natural habitats we are into. And often, that involves using rocks. Well, not that often, actually, now that I think of it...However, on those occasions when I DO use rocks, it can be fun... 

I mean, usually.

But, like, one or two rocks isn't exactly "aquascpaing with rocks", right?

And that's typically the extent of my work with rock these days...The sad truth is, I'm not particularly good at it! Now, you'd think that, being a reefer, arranging rocks would be second nature, right? 

Well, perhaps.

Nah. I admit, I suck at it. 

Even when I was a reefer, where rocks are the whole game in aquascaping...I sucked at it, for the most part. The only saving grace for people like me is that the corals will grow to over over whatever "rockwork" you create! So, if you grow nice corals, you still look like an aquascaping genius! 

I mean, sure, I can create a little pile here and there.

I can replicate a reef, maybe create little areas of rock reminiscent of those that you'd see in a stream...But those "artistic", Iwagumi-style rock arrangements or carefully thought-out hardscape featuring rock...

No chance. None at all. Like, zero.

That's why I lean on my friends to do the work when I want serious use of rock in something, lol.

Leaves? I'm fearless...I'd dare say, I am a master at them, lol. Seed pods? Easy- I'm in my element! Driftwood and twigs and such? Totally. I mean, I'm no George Farmer, Jurjis Jutajevs, Cory Hopkins, or Johnny Ciotti- but I can come up with some stuff that works...

But, rocks?

I love them.

I love those Iwagumi scapes. I love bold scapes which seem to effortlessly integrate rocks into the wood and other elements.. 

I mean, I admire them greatly.  I'm sort of in awe of the skill of those who create them. I just have zero interest in doing them myself. I'm not much of a "technical 'scaper."

And, if you think about it- pretty much every aquarium which I've done and shared with you on these pages pretty much doesn't feature a single rock in it! Ever notice that?

So it IS kind of funny to walk into my facility and look at all of the rock we offer for sale, and think to myself, "It's totally beautiful...But I have no idea how to use this stuff!"

Yeah, that's some brutal honesty! 

Now that Tannin has evolved from just a "blackwater specialist" to more of a "natural aquascaping specialist", providing inspiration and materials for a wide variety of habitat replications, it's neat to take a fresh look at materials like rocks. And very therapeutic for me, actually!

It's fun to think of rocks as vital components of aquariums modeled after Nature. There are so many possible combinations and possibilities to create amazing stuff with these simple elements!

And, it's also important for us to explain why we typically don't see rocks in some of our fave blackwater habitats, like the igapo- the seasonally-flooded forests of Brazil. There are some reasons that make real sense!

The "whitewater" rivers of South America rush quickly down from the mountains of Peru and Bolivia, too rapidly for clay and silt to be stripped from them. The rocks from these mountainous areas offer minerals and nutrients such as nitrogen, attached to the silt and clay, and minerals like illite, montmorillomite (hey, we know that one from shrimp geeks!), and chlorite, to nourish the lower-lying areas.

In these areas, numerous microbes and plants consume some of the nitrogen, and while eaten by other organisms, convey what's left to the even lower-lying forest habitats.

The Amazonian blackwater rivers are largely depleted in nutrients, having passed through the lowland forest soils as groundwater, from which weathering has already occurred. "Hydro-geomorphic processes" ( i.e.; a fancy way of referring to part of the stuff that makes rocks!) are far less intense than they are in the upland, mountainous regions of The Andes, with their abundance of minerals, nutrients, slits, and sediments.

In other words, the result is that most low-lying Amazonian forest soils are really low in nutrients. The soils are nutrient-poor, acidic "podzols..." It's been suggested that most of the available nutrients are taken up by the root mats of the dense plant growth in these forested areas. And even the rainwater provides little in the way of nutrient for the plants which grow there.

However, what little nutrient there is typically returns to the soils by means of leaf drop from the trees which grow there. And of course, when the water returns to the forest floors, what little nutrient remains is released into the waters, too. And it's quickly utilized by the resident microorganisms.

Serious nutrient cycling, right?

I'm no expert-or even a novice- on geology or geochemistry, or anything in that subject area, for that matter....However, based on my research into this stuff, it goes without saying that these are hardly conditions under which rocks as we know them could form.

Now, you might find the random rock in the igapo that was washed down from the Andes or some other high-country locale in these forests, but it did not evolve there. This also helps to explain why the blackwater habitats are generally low in inorganic nutrients and minerals, right? 

Yet, you might find areas of rocks which have accumulated, into which blackwater streams and rivers might overflow into. These would be cool potential niches for us to replicate in aquariums, huh?

However, if you're really, really hardcore into replicating an igapo in your next aquarium, you'd probably want to exclude rocks...

I've pretty much obsessed over this particular habitat; I can't help but wonder if there is subconscious bias I have against rocks- and THAT is why I never scape with them?

Nah! Couldn't be.

Well, maybe?

On the other hand, with all of the delightful possibilities that nature offers for us to replicate unique natural habitats in our aquariums, utilizing rocks in your 'scape is just a cool thing to do, huh?

A little research, a little practice, and a bit of sleuthing about the natural aquatic habitats  of the world can yield remarkable amounts of inspiring information! And we know a place where you can find some really cool rocks, when the muse hits...

Leaves. Wood. Water..Life. And ROCKS. All working together.

I love rock. I LOVE rock. Must convince myself... 😂

Hmm...I'm going to go down and look at our rock bins again. I know I suck, but I have this idea that I've been meaning to try...It might work this time...

Stay creative. Stay inspired. Stay persistent. Stay thoughtful...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

Scott Fellman
Scott Fellman


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