We've talked about the idea of "clear water" botanical-style aquariums before. In other words, aquariums in which botanical items are utilized, where the water remains clear, not amber-to-brown-colored, but it is something that we as a group tend to look the other way on, which I think is funny. I mean, a few years ago, you were considered sort of odd by the aquarium world for wanting brown water. Now, in our community, NOT wanting brown water is often looked on a bit strangely, lol.
On the other hand, it is absolutely possible (and entirely realistic) to have an aquarium with botanical materials that does not have the lovely "cafe au lait" look that we all know and love so well!
In a twist on one of our own marketing slogans, "It's okay NOT to tint..."
Although the three "classical water types" (white, black and clear) are used by science to describe many of these habitats, aquarists tend to classify water as "blackwater" or "clearwater", which, although not scientifically "pure", tends to make our understanding and discussions easier!
And the reality is that there are many, many habitats throughout the world which have tons (literally) of botanical materials in them, yet have relatively clear water. It's certainly not a given that the presence of leaves, wood, and other botanical materials in a given body of water will result in brown water and low pH. Rivers like the Juruá, Japurá, Purus, and Madeira) are turbid, with water transparency that varies, and they transport large amounts of nutrient-rich sediments from The Andes. Their waters have near- neutral pH and relatively high concentrations of dissolved solids.
The Rio Xingu and Tapajós are classic examples of "clearwater" rivers. One of the largest tributaries of the Amazon, the "Xingu" has an abundance of rock, and a higher content of dissolved minerals than a blackwater habitat like the Rio Negro. There is not much suspended matter because the rock formations which the river courses through are ancient and no longer erode in the current. The pH varies between 6 and 7.
As we've mentioned many times, water color, although helpful to us aquarists in some respects, is not an absolutely reliable indicator of the pH or ionic composition of the water! There is no substitute for good, old-fashioned water testing!
Interestingly (and perhaps, confusingly) the lower section of some Amazonian black-water rivers such as the Rio Negro, Tefé, Uatumã and Urubu in Brazil; Nanay in Peru and some streams in Colombia can have ionic composition and/or pH-values similar to the white water rivers, and not like the typical Amazonian blackwater rivers. It is though by researchers that low electrical conductivity values can be responsible for this phenomenon.
In addition, it's though that many rivers and streams have to be considered as “mixed waters” resulting from the influence of tributaries with different physical and chemical properties of their waters.
As if we don't need more confusion, right? Talk about "muddy waters!"
So, for us aquarists, the arguments and discussions can rage on and on and on, and aquarists who have been to various parts of these rivers may observe somewhat different characteristics than others...and be 100% accurate in their findings! Generalizations, although often a "no- no", may actually be useful to us. (gulp)
The implications of all of this stuff are that, if you're looking to accurately recreate the water conditions from which the specific fishes you keep come from, you would be well-served to determine, as accurately as possible, where they originated from. With wild-collected stock this might be easier (assuming the collectors/distributors possess and make this information known (Hear that guys? A good idea!) to hobbyists, the ultimate "end users" of their "product' (that sounds awful, calling fishes "product", but I think you get the point...)
How do we achieve "clear", "botanically-enhanced" water? Well, of course, you can start of with water with minimal dissolved solids (RO/DI) and you can prepare botanicals and use them as you see fit to accurately represent the topography of your subject body of water. However, you'd likely use significant applications of chemical media, such as activated carbon, to remove the "tint." And of course, buffering substrates or rocks as needed, in more neutral situations.
We know from experience that some botanicals are less likely to impart significant visual tint to the water, simply because of their composition. The "harder" materials, like "Jungle Pods", "Save Pods", "Heart Pods", etc., although perfectly capable of leaching some tannins into the water, seem to impart significantly less color than materials like leaves, or softer, more fibrous botanicals like "Rio Fruta", "Ceu Fruta", "Coco Curls", etc.
Now, there are numerous approaches to preparing water for our aquariums, and many, many different viewpoints and ideas among hobbyists as the "best" way to do things. However, at the end of the day, we all need to operate in a manner which we can understand, consistently replicate, and are comfortable with. And so much of this comes with education, discussion, and sharing of ideas.
This brief, highly-generalized discussion was not intended to be the last word on this topic. Merely a brief introduction of some "talking points" that we as hobbyists can use for further research and discussion for this interesting and most important topic.
There is so much to learn, and even more to experiment with in the context of our botanical-style aquariums!
Stay curious. Stay creative. Stay thoughtful. Stay open-minded.
And Stay Wet.