Managing the Murk: How I learned to stop worrying and love the mud!

As most of you know by now, I'm a huge fan of decomposing botanicals, tinted water, wood covered in biofilms, occasional turbidity, and general accumulations of botanical detritus in my tanks. I've learned not to freak out about it; rather, to embrace this stuff as part of the "functional aesthetics" of the botanical-style aquarium.

Often, the decisions we make at the earliest phases of setting up our tanks will create impact many weeks or months down the line...Sort of like little "Easter Eggs"- things occur long after we start up our aquariums- which fundamentally surprise/delight/frighten us as they show up and influence the aesthetics and function of our tanks!

It's part of the game.

Reefers see this when coralline algae grows on exposed surfaces, or when macro algae or "hitchhiking" corals unexpectedly sprout from live rock months after the aquarium is established. Planted aquarium people experience similar surprises when that long-forgotten stem of (insert plant you though died off here) suddenly sprouts forward, seemingly from nothing, to grace your aquascape. 

Occasionally, seemingly negative things happen- such as unexpected micro algae/diatom blooms ("Hmm, I guess that piece of rock DID have a crap-load of phosphate in it after all!"), plant growth patterns, water-flow issues (setting that big piece of dogwood in the corner by the filter return seemed like a really good idea at the time...). Sometimes it's because of something we never thought about. Other times, it's a direct result of the decisions we made when we set up the tank.

And of course, when you're dealing with the impact of these things, you're faced with two basic choices:

"Correct" them...or live with them.

Now, "corrections" sometimes are extremely difficult, involving a dismantling of infrastructure or aquascaping to effect the change you want.  And they may not always garner the desired result right from the start. Other times, it's as simple as moving that piece of rock out of the way. Usually, it's somewhere in between. And of course, all of those little changes may impact the look and function of your tank- usually for the better...but not always- right?

And if you decide to simply "leave it alone" and "deal with" the consequences, there are two possible outcomes: 1) Your tank will never function as you envisioned it, and the problems caused by the issue will simply increase  OR,  2) The aquarium will "correct itself" and evolve to a better place with minimal intervention on your part (often just continuing maintenance practices or whatever that you're already doing...).

Long preamble to reach a recent personal example, but here's one for you:

As you no doubt have seen by now, I finally set up my brackish water/botanical-style mangrove habitat aquarium. It's been a really fun project, and it is great to see it evolving along.

When I first started, one of my "must haves" was the inclusion of "biosediment"/mud i the substrate mix. Now, I knew that, since I wasn't initially planting the substrate with rooted, brackish-tolerant aquatics, like Cryptocoryne ciliata, that the substrate would serve little purpose initially (until the prop roots of my mangrove propagules "touched down" into it months after the tank was established), other than to "enrich" the overall ecosystem of the tank. 

Okay, "enrich" is one of those deliberately vague "buzz words" I love to play with...I mean, WTF does it really mean? Well, I like to think that it means that it will impart minerals and organics to the water which would foster the growth of bacteria, beneficial microorganisms, and potentially, some small crustaceans which would help establish a little "food web" in my tank.

Now, curiously, it seems to have done some of that! I've seen an interesting explosion of small life forms. And the addition of mangrove leaf litter has no doubt assisted in fostering this. The small life forms in the substrate region seem to have been busy breaking down the leaves and other matters into a rich "compost" of sorts. Although there isn't very much of this visible in the tank, it's there- and the Olive Nerites snails which I've populated the tank with have certainly seemed to appreciate this "diversity", and spend much time grazing on the substrate! 

The other wild card, if you will, was the inclusion of mangrove root and branches into the hardscape. Both of these materials will impart organic materials into the water. Quite frankly, even though I love the stuff, I personally believe that mangrove root wood is really "dirty"- and you'll see a release of "stuff" locked up in the wood tissues over time that is different than that I've experienced with other types of woods we use in aquariums.

Of course, with all of the "functional benefits" of these kinds of materials, you'll also experience some stuff which challenges your long-held aesthetic beliefs about what a "successful" aquarium looks like. In the same manner in which leaves and botanicals get covered in biofilms and break down, "dirty" wood and rich substrates can do their own "editing" to your tank's look

I focused on the substrate in this situation as the source of this cloudiness.

I used a mix of several materials, such as marine biosediment, CaribSea "Refugium Mineral Mud", "Miracle Mud", and even a touch of pond soil, capped by some dark fracted clay substrate...perhaps not enough of it- a mix you'd definitely be interested in if you're growing aquatic plants- but a substrate which, if disturbed, is almost certainly a recipe for some cloudy water! 

And that's exactly what I experienced. I realized that my inclusion of an external Vortech MP10 pump to create "intelligent" water movement at every level of the tank would no doubt disturb the substrate a bit. Combined with the activities of some bottom-dwelling fishes like Bumblebee Gobies and the slow "excavating" on the surface of the substrate done by the snails, it was a certain recipe for...some turbidity- cloudiness, if you will.

It's something I kind of knew would be an issue going into this setup. I mean, not completely positive, but pretty certain. And quite frankly, I wasn't 100% convinced how long it would last, or if it would ever go away. I mean, it's a fairly deep substrate in some that's a big "supply" of sediments that could potentially cloud the water. As a long-time reefer, I always thought about crystal clarity of water as being a sort of "measure" of overall water quality...which, of course, isn't really a complete story. You can have turbidity and high water quality, right?

Depends what's causing it.

And besides, I needed to see what it was that was causing the cloudiness, and what impact on water quality it was having.

So, what to do? How to cope with this?

Well, it was pretty straightforward to me: First, ascertain exactly what was going on. I did the "sniff test" to see if one of those obvious and classic "bad news" scenarios of bacterial blooms or other pollution is immediately apparent.

Nope. No smell!

Now, I've been in the game long enough to know that smell isn't the whole game, so a full "suite" of basic water testing (pH, nitrite/ammonia/nitrate/phosphates) was undertaken...The results were no nitrite and ammonia, and virtually undetectable nitrate and phosphate. The latter two are generally agreed to be a good "biological yardstick" of aquarium water quality, so it kind of made sense.

And I kind of figured that was the case.

I felt that it was a direct result of the decision to include very fine sediments/mud in my substrate mix.  Now, you could look at the potential "negatives" of this turbidity (umm, mainly that it looks kind of...well, shitty to many!) and think that this is a huge problem. Or, you could embrace it- much like we do in our blackwater/botanical-style aquariums with their "look"- as part of the "functional aesthetics" of a rich, active substrate in a dynamically-evolving aquarium. These episodes seem to wax and wane over time, too.

If you look at some of the surface level and underwater photos of mangrove habitats in nature, you'll see this similar "haziness" as well. Now, not all of these environments feature this haze, and an aquarium is a closed system without the benefit of trillions of liters of water for dissolution- but the analog is, ahem- clear to me!

And curiously, I've noticed these kinds of phenomenon before in my aquariums which utilized mud-based substrates. And often, the cloudiness dissipates over time. It could be could also be a bloom of microorganisms which are flourishing in in the water as a result of the organic materials from this sediment. Obviously, a micro-assay or other more focused study would be far more conclusive.

However, I think that the critical part of this equation is how we think about this stuff and accept it into the "big picture" of the management and "lifetime" of our aquarium systems- and how we react!

In my situation, the options I had were pretty straightforward: I could flat-out dismantle the aquarium and re-set it without mud. Totally unacceptable to me. Or, I could keep the system running and continue to do regular water exchanges, utilize micron filter socks, and chemical filtration media. Essentially, dong "nothing different" to address the issue. Consistency. Patience. Acceptance.

And that's what I did. I kept doing what I was doing. And interestingly, the cloudiness subsided substantially after about a week. Kind of like I thought it might.

Go figure.

So, the short point of this long-winded and meandering discourse is that you will often experience "stuff" in our botanical-style aquariums which requires us to make a bunch of mental shifts, acceptances or other changes in our thinking. An ability to release ourselves from the expectations and preconceptions that we've cultivated in the hobby for generations is required when you're playing in unconventional areas. 

Or, you can break stuff down and start over.

It's a choice.

And a personal one, at that.

This was a quick look at how I learned to stop worrying and love the mud. 

Stay bold. Stay engaged. Stay consistent. Stay curious...

And Stay Wet.


Scott Fellman

Tannin Aquatics





Scott Fellman
Scott Fellman


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