Game of Cones...yeah, had to.

[Tannin Aquatics]

Like many of you, I love the golden brown tint that leaves and botanicals impart to the water in my aquariums. And I love the fact that there are more than one way to get it!

Aquarists have used cones from various deciduous hardwood trees, such as Alder (Alinus), Birch (Betula sp.) and more recently, Indian Casaurina trees to condition water for various species of fishes. These little cones, each which appears a bit different, also seem to have slightly different effect upon the aquarium water in which they are steeped.

Some hobbyists and vendors have attributed seemingly "magical" powers to cones, such as the ability to cure fungal infections, reduce incidence of egg fungus in fishes, etc. I've never seen any hard data to support this, nor have I seen anyone recommend a "dosage" (either number of cones per gallon or mg/l of "cone solution") that can reliably and consistently achieve the affects enthusiastically attributed to these cones, so for now, I'll recommend them for what I feel are their proven "applications"- imparting tannin to aquarium water and providing some aesthetics, as well as supplemental feeding for some animals.

Let's take a brief look at the most commonly encountered cone types used in the aquatic hobby.

 

The most "traditional" standby, the "Queen of The Cones", if you will- Alder, is pretty potent from a tannin-producing standpoint, imparting a nice tint to the water at relatively modest "doses" (like 6 cones for every 10 gallons of aquarium capacity, in our experience). Of course, the amount of color they produce and tannins they impart is variable, subject to a wide range of factors, such as the characteristics of the tank water, etc., so you'll have to experiment and use our recommendation as a good "starting point" for working with them. Alder seem to be the least "durable" of the cones we work with, breaking down physically after just a few short weeks. In addition to their "tinting" capabilities, they are often grazed on for biofilm, and fed upon directly be many Neocaridina and other ornamental shrimp.

Birch cones are an excellent, more durable substitute or supplement for Alder cones, as they seem to last a bit longer when submerged, and impart a similar amount of tint to the water when used at a "dose" of around 6-8 cones per 10 gallons of aquarium capacity as your "starting off" point. Being slightly more "durable" than Alder cones, they are really cool to use as "media" in a fluidized reactor,to more thoroughly mix with the water and impart their tannins to it; they tend not to break apart as easily as Alder when used in this capacity. Like their counterparts, Birch cones are also "fodder" for many species of ornamental shrimp, which feed on the biofilms they might attract, as well as directly upon the cones themselves as they break down.

Casaurina cones are relatively new to the scene, and have a decidedly different "look" to them. Not that looks are important with cones, but they are easily distinguished from the Alder and Birch cones, looking almost like miniature pineapples! They pack a very respectable tannin-production capacity as well, and seem to last longest of all, both in terms of structural "integrity" and ability to continuously release tannins into the water. Their highly "faceted" morphology gives them a lot of surface area, which is good for both releasing tannins and for providing a feeding "substrate" for shrimp and perhaps some xylophorous fishes (We've seen Loricariids of various species feeding directly on Casuarina and other cones on many occasions).

Preparation of cones for aquarium use is an important step, as they can accumulate a lot of foreign material (mainly small particles of dirt and dust) which should be removed before submersion. This is easily accomplished by a quick rinse in warm water. Being ever cautious, we also recommend that you "steep" them a bit (like 20 minutes or so) before use. This will soften them up a bit, making the release of the bound-up tannins contained within their structures a bit more rapid. Oh, and they smell amazing when they're wetted for the first time!

Utilizing cones in your aquarium is pretty straightforward. There are essentially three ways that you'd want to employ them. First, you can simply toss them into your tank after preparation.

This is easiest and most common, although many aquascapers may not like the aesthetics (I personally think they look "out of place", myself). Obviously, if you're a breeder or shrimp keeper, the aesthetics may be a secondary concern, so it's your call here. And of course, if they're being used as a Pleco or shrimp "chew toy", this is the logical approach!

The other way to employ cones is to use them "passively" as "media" either in your canister filter or other part of your aquarium where the water will flow through them easily in a mesh media bag. This gets pretty good water "flow through" over the cones, taking great advantage of their tannin-releasing capacity. 

Finally, you can place them in a reactor, as outlined above, which gives superior utilization of their surface area and ability to release tannins into the water column. There are a number of different inexpensive in-line reactors on the market that you might want to investigate for this application.

As 'tint vehicles", cones are pretty cool little "packages", providing a fair amount of "bang for the buck", ease of use, and effectiveness. The amount of tint they impart to the water may not be quite as significant as say, Catappa leaves; however, they contain a nice "dose" of tannins, making them a viable alternative once you figure out the amount you need to do the job in your particular application.

We hope you've gotten some value out of this brief little foray into the concept of using cones for your aquarium. With their small size, versatility, and relative "longevity" when submerged, cones are a great alternative to leaves when the "tint" is desired without the presence of these other materials within the aquarium itself. If you have other thoughts or techniques on employing the various cones for aquatic use, we'd love to hear from you!

Stay inventive. Stay engaged. Stay "tinted!"

And Stay Wet.

 

Scott Fellman

Tannin Aquatics