We obsess about creating representations of blackwater environments a lot around here, huh?
Can't help it. We love 'em!
However, I was thinking about this the other day: We talk a lot about setting the stage below the waterline...what about the influence of the environment above?
You know, light...
Yeah, how we choose to illuminate a blackwater themed tank can definitely impact its aesthetics, operation, and overall functionality.
In a typical rain forest, it's estimated that as little as 5% of the sunlight reaches the "floor", so it goes without saying that any stream or creek under the canopy of trees is not getting that much light!
So, it goes without saying that in an aquarium where you're trying to replicate one of those hidden "igarapes" (literally "Canoe Way" in the indigenous language of the region), without a diversity of light-demanding aquatic plants, you really don't need to worry about providing a ton of bright light.
Rather, it would make more sense to apply "spot" lighting or dimmed lighting from a format like LED, which gives you more control over color and intensity than most other lighting methods. Or, you can use "room ambient" lighting an call it a day!
There is so much to learn from managing a system set up to replicate one of these environments, and it is helpful to look to nature once again to help us make decisions. Without tons of excess light hitting your aquarium, the incidence of excessive algal growth is definitely limited, which is important when you take into account the decaying leaves and other botanical materials present in these environments.
Just another thing to think about when contemplating setting up an aquarium to replicate this unique environment!
Stay curious. Stay excited.