The world of blackwater/brackish botanical-style aquarium has its own set of "norms" and ways of doing things, doesn't it? And since this little sector of the hobby has become more and more noticeable and apparent in the grander scheme of things, we've seen more and more observations, refinements, and techniques developing around our hobby.
Because of the very nature of aquatic botanicals and how they interact with their environment, you need to regularly evaluate, scrub or even replace them as needed. You'll need to understand the progression of things that happen as your tank establishes itself. And, perhaps most important, you'll need to make some mental "adjustments" to accept and appreciate this different aesthetic.
There has been much discussion here and elsewhere about the various "stages" which our botanical-style aquariums go through as they run in. We understand that the materials we use will interact the aquatic environment directly, imparting tannins, humic acids, and other organics into the water. We like to call aquatic botanicals "dynamic" materials, as they are hardly "static" or "inert" in nature!
And the fact that these systems are actively evolving means that you need to "manage" them with some common sense practices. Which, really, is no different, no more challenging, and probably even less mentally taxing than say, a "high tech" planted system, reef aquarium, or a specialized breeding setup for fishes like Wild Discus or Angelfish.
And there is a "progression" which takes place as your botanical-style aquarium evolves in its early phases. I think it can be broken down into a few distinct phases. And, I thought this might be a good time to comment on these phases, and what to expect; what to do:
Startup-first 3 weeks: Obviously., a lot is happening during this seminal time! You should observe your botanicals to make sure that they are remaining "negatively buoyant" (i.e.; waterlogged!). Remove any which appear to be floating or present a putrid, "rotten egg-like" smell. Depending on your water chemistry, density of botanicals, the specific ones you've used, and the filtration media employed, you'll start to see the "tint" usually after a few days, reaching it's maximum after about 3 weeks. Perform regular water changes and other maintenance like you would on any other aquarium during this time.
Early "evolution"- One month- two months: This is when you'll likely see some biofilms and even some algal growth on the botanicals. This is the phase where the tank is really coming "alive." Some hobbyists strongly dislike the appearance of biofilms and true algae...I get it! What to do? You can physically scrub the biofilms off of the botanicals as needed, or employ "biological controls" (such as shrimp, snails, or even Otocinculus catfish) to help with this process.
Although they are efficient, you shouldn't expect the animals to get everything. You can assist with the removal of any "offensive" growths, or...wait it out. This is the "mental shift" phase. A time where you accept that you're working with a different type of system- one which embraces nature in all of its diversity.
Two months-four months: By this time, your aquarium has no doubt settled into a comfortable, more stable situation, and you've come to appreciate the more natural appearance of your system. Some of the softer, more "transient" botanicals, such as leaves, have typically broken down significantly at this point, and no doubt need replacement. You employ regular maintenance practices, such as water changes, filter cleaning/media replacement, etc., and monitor water chemistry parameters like you would in any other tank.
By this time, you'll come to recognize what is "normal" for your system, and any deviations from the norm will become more obvious to you. You can "top off" your system with some newly-prepared botanicals as you see fit. This is where you'll no doubt develop your own routines for this. We love this time, because it's where the nuances of long-term botanical-style aquarium management are developed and perfected!
Although this short summary of the progression of the early stages of a botanical-style aquarium isn't intended to serve as the definitive guide on what will happen with your tank, it IS a sort of "quick start guide" as to what typically happens during the early life of such an aquarium. A "quick reference" of sorts, about what may be expected from a typical botanical-style system.
Your experience may vary slightly; however, these observations were made based upon my own experiences and others who work with these types of aquariums. There are many factors, such as your base water chemistry, maintenance practices, filtration, etc., which may skew the timeline, and the progression may be longer or shorter, but the "markers" are typically the same.
Probably the most significant "adjustments" you need to make are mental ones.
You need to accept that this type of tank will look fundamentally different than other types of systems you've maintained. Obviously, the tint of the water is the most obvious. This can be managed, to a certain degree, by employing activated carbon. Purigen, or other chemical filtration to remove some or all of the "tint" as desired.
And the biofilms?
The realization that their appearance is perfectly natural and entirely consistent with the nature of these environments to have some of this stuff present is little comfort to you if you just can't handle looking at a field of "yuck" on your botanicals. I can't stress enough the need to make that "mental shift."
As we discussed, management of this stuff is entirely up to you and what you can tolerate. Generally, biofilms and algae are self-limiting, ultimately disappearing or diminishing substantially over time as the compounds that fuel them diminish or attain levels that are not sufficient for their continued growth, or as a result of animals consuming them- or a combination of both.
Fishes will interact very naturally with your system, too. The decomposition of "transient" materials like leaves and softer pods, etc. is simply part of the natural dynamic, and will continue as long as you choose to employ these materials in your aquascape. If you observe carefully, you may note spawning and other "grazing" behaviors in your fishes, and note that they are spending significant time foraging though the broken-down matter, much like in nature.
There is still so much to learn; so many "mental shifts" that we need to make...However, the progress we've made thus far in this exciting branch of the hobby is amazing. And so many discoveries- and even breakthroughs- are occurring right in your own aquarium...As you begin to understand and evaluate your own aquarium, you'll gain a greater appreciation for the wonders of nature and the processes that have occurred for eons.
Stay observant. Stay diligent. Stay engaged. Stay humble...
And Stay Wet.