So we're coming up on a year since we've actively marketed our aquatic botanicals to the aquatic community, and we're starting to get good information on experiences from our long-term users. Every day, it seems like we're seeing pics of cool new tanks and ideas that our fellow "tinters" are working with!
One of the most frequently asked questions we receive is, "How long does ______ last in the aquarium?"
A very good question, because the answer is subject to a lot of variables. The reality is that many of the botanicals last a surprisingly long time, depending upon how you feel about having them in your system as they start to break down!
Of course, leaves are definitely the most "ephemeral" of the botanicals, with most lasting a few weeks before starting to break down significantly. Catappa leaves are probably the fastest ones to soften, often starting to decompose in about 2-3 weeks, whereas Guava can hang around for a month before it starts to break down. The next most durable leaves are Loquat, followed by Jackfruit leaves, which typically hang on over month or more before breaking down significantly. The long-duration champ to date has been Magnolia- I've had some leaves with me almost intact for 4-6 months before they really start to soften!
And I think it's important, when considering how long botanicals "last", to think about what you are okay with from an aesthetic standpoint. I mean, I will typically hang on to a given leaf in my aquariums until it's pretty much "compost"- stringy and broken apart. I kind of like the "natural" sort of look, although once it starts dropping off bits and pieces that get scattered around the substrate, many hobbyists "call it" and remove the offending leaf (or leaves) and replace. It's really up to you.
The leaves will impart their tannins, humic acids, and other organics from day one, yet I honestly couldn't tell you how long they'll keep pushing out tannin into the water. I will look into this and speak to some botanists to see if the tannins are present throughout leaf structure, or only in the dermal layers.
I have a hunch that the bulk of the tannins from leaves are present in the dermal layers. (meaning, that when the dermal tissue is gone, the "skeleton" of the leaf may not impart any significant tannins. At that point, it's providing other organic matter, which you may or may not care to have. At some point, I would imagine that a leaf would essentially become "inert", but I'm merely speculating.
A good rule of thumb for a lot of hobbyists who play with leaves is to replace them when they see the "tint" starting to "fade" a bit...As one who continuously replaces or adds new leaves, I have not really experienced that phenomenon! And, when you think about it, a continued regular addition of new leaves is analogous to what happens in nature, with new leaves falling into the water as older ones decompose.
If you like the aesthetic of freshly fallen, relatively intact leaves, then it's a "no brainer"- you simply replace 'em as they start looking more "weathered" than you care for. Thus, you can have a continuously changing, yet "pristine-looking" leaf litter bed.
Hobbyists like me who like a mix will simply add new leaves as they see fit. Still others will take different approaches- for a more "maintenance free' leaf litter bed (other than occasionally removing biofilms or any hairy algae if they become too offensive), simply go with one of the longer-lasting leaves, such as Magnolia or Jackfruit as your dominant, if not exclusive leaf.
From the perspective of the other botanicals, such as seed pods and such, it's kind of a similar mentality: You can continuously replace with pristine pieces, or let them remain until they break down to he point where you no longer find them attractive. Many of the "harder" pods, like "Jungle Pods", "Savu Pods", "Lampada Pods", and "Heart Pods" will hang on for many, many months...I've actually had some specimens for years- before they soften to the point of losing their structure.
Again, removal of these botanicals is more based on your aesthetic sensibilities than any particular necessity. Obviously, if a given piece is going foul in your tank, giving off a noxious, hydrogen sulfide-like smell, then remove it at once. However, the bulk of the botanicals, if properly prepared before use, will last surprisingly long times. You might need to occasionally brush them gently to remove any build up of biofilm and/or algae, but that is typically all you need to do over the long haul.
You can, of course, get some "assistance" in maintaining your botanicals from little fish friends like Otocinculus catfishes, as they seem to love devouring any algal films that crop up on the surfaces of the botanicals!
And of course, many of the cool ornamental shrimp that we keep will also do a great job of both keeping botanicals free of biofilms and algae, as well as helping further break down materials like leaves and "softer" pods and such.
Items like "Coco Curls", "Terra Sorrindo", and "Rio Fruta" last a remarkably long time, given their seemingly not-so-robust structure, and really look fantastic as they age within the aquarium, IMHO. I've had specimens of each of these make it to the one year mark (longer, in the case of "Rio Fruta'), and they still look pretty good.
Again, replacement periodically of any of the more durable botanicals is totally up to you. Since many of these items impart significantly less in the way of tannins (fro ma visual standpoint, particularly), the real consideration would be if you like the look as they break down.
At the risk of sounding like a broken record, I will implore you once again to follow the two most basic "rules" of using aquatic botanicals in your aquarium:
1) Take the time to prepare everything you add to your tank. Rinse, boil, or soak as necessary and give a quick rinse agin before you place them in your tank.
2) Go SLOWLY and add just a few specimens at a time, particularly in established aquariums with delicate fish and/or heavy bioloads. Adding large quantities of ANYTHING, particularly materials like botanicals, which do break down and do impart tannins and humic acids to the water, can affect the environment, especially in smaller volumes of water, or systems with very soft, acidic conditions.
Testing your water for the basics (ammonia, nitrite, pH, alkalinity, and probably phosphate and nitrate) is always recommended for ANY aquarium- yet I think it's a very good idea for a botanical-influenced one, because you are adding boiled to your tank. You need to assess your environmental conditions regularly regardless of what type of approach you use; in my opinion, it's almost essential when adding materials such as botanicals to your tank. And of course, there is no substitute for simply observing your fishes and seeing how they interact with and react to the environment you've created for them!
In my experience, and in the experience of many other hobbyists who are playing with "New Botanical"-style aquariums, they are no more difficult or challenging to maintain than most other types of systems we play with, such as live planted tanks, Rift Lake cichlid tanks, or reef tanks. You simply need to apply common sense, patience, and good observation. Over time, you'll learn what is "normal" for your aquarium, like you would with any other approach.
You will need to make the "mental adjustment" of seeing brown water, biofilms, some algae on occasion, and decomposing botanicals in your aquarium. Some people find it ugly, preferring the more pristine look of a "traditional" aquarium. Many hobbyists, however, have discovered a whole new aesthetic with these types of aquariums, creating a truly natural-looking aquarium unlike any other.
Understanding and appreciating the unique environment, interactions, aesthetics, and potential downsides is extremely important. Like any aquarium, a "New Botanical"-style system can provide endless enjoyment and relaxation, once you get a feel for how they operate. If you're "on the fence" about trying an aquarium like this, you should definitely at least give one a try with a small tank, to get a feel for the concept and see if you like it.
One word of warning: If your like many hobbyists who tentatively experimented with a small tank to see if they liked the idea, you might be finding yourself shopping for a new, larger tank as you decide to "scale up" the concept...it's addictive!
Until next time...
Stay inquisitive. Stay open-minded. Stay on top of things.
And Stay Wet.