From whence the water comes...

It goes without saying that the single most important component of our aquariums is also the most obvious...water! As the literal bearer of life and environment in which our fishes, plants, and other organisms thrive, it's fundamental.

And I dear say that we take it for granted a bit.

Have you ever thought of how water actually gets into those bodies of water (streams, rivers, etc.) that we find so compelling?

Well, sure, the first two things that come to mind are precipitation and runoff from the higher mountains. And that's perfectly logical and correct. However, if you consider some of the other  processes by which water makes it into our favored habitats, it's actually quite interesting, and maybe even has implications for the way we prepare water for our aquariums.


Sure, some simply falls into the body of water directly from the sky, and that's that. Some is a result of overflowing streams and rivers (like, ya' know- those flooded Igapo forests we talk about!). Inputs of precipitation falling over the area of an aquatic habitat are transferred to the habitat via a number of different pathways.

It's surprisingly complicated.

There's like a whole field of science devoted to studying this process! 

However, not all of the water has such an easy journey on its way into our favorite aquatic habitat!

Even in the case of rainwater, some of it simply lands on tree leaves in the surrounding area and evaporates. This is a process scientists call "interception", and accounts for the fact that not all water makes it to the ground. Water that does reach the ground enters the soil through a process called infiltration. slowly percolating down to soil areas known as the "saturated zone"- and as you'd imagine, this is where the fun really begins! (to a soil geologist, at least!)

The soil properties control the infiltration capacity; these include things like soil permeability, the presence of vegetation and plant roots, and how much water is already in the soil. Through what is known as "ground water flow", ultimately, the water finds it way into our favorite aquatic habitats. Soil texture ( the relative proportion of sand, silt and clay particles within the mix) affects infiltration rates. 

Sandy soils like the "podzols" that we've talked about have higher permeability than some clay soils. In some really arid areas a "crust" can form on the soil surface, decreasing the permeability. And of course, the thickness of the soil directly affects how much water the soil can actually absorb.

During that journey into the (aquatic) habitats, materials like humic substances, minerals, etc. will be absorbed into the water from the surrounding soil. Yeah...that's the interesting part: The surrounding geography and geology have as much to do with the ultimate water characteristics as anything else! Like so many things in nature, everything is somehow interrelated!

Once again, bringing it all back to a more practical aquarium point of view, I can't help but wonder if working with different types of substrate materials (soils, sands, etc.) in our "makeup water containers could yield some similar effects to those we see when we steep leaves and botanicals in the water. Could the right combination of soils in both our makeup water containers and even in the aquarium create even more realistic water conditions for our fishes and aquatic plants?

One can only wonder...

It makes a ton of sense.

We're seeing more and more specialized "aquatic soils" for plants which are designed to simulate some of the natural habitats in which they are found. Well, fishes are typically found in those habitats, too, right?

Why should the plants have all the fun?

( you want us to carry this stuff? -S.F.)

Wouldn't it make sense to utilize some of these specialty substrates in tanks which feature fishes and not just plants (or even devoid of plants?). What potential benefits for our fishes could be gained by using these more "technical" aquatic plant substrates in our fish-centric botanical-style blackwater aquariums? 

With water finding its way into the streams, rivers and other areas from so many sources, there is probably so much we can learn from finding out more about the surrounding areas  themselves, and how water ultimately makes it into the bodies of water we are so obsessed with.

Wouldn't it be interesting, when contemplating more natural biotope/biotype aquariums, to study and take into consideration the surrounding geology and  

Today's simple thought, with complicated mechanisms, and broad implications!

Something to give some serious thought to, right? Who's into experimenting with this?

Stay intrigued. Stay curious. Stay innovative. Stay engaged.

And Stay Wet.


Scott Fellman

Tannin Aquatics 





Scott Fellman
Scott Fellman


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