"That peat moss thing"...again...


After a bunch of years playing with botanicals, we've learned a lot of stuff. We've screwed up a lot of stuff, too! Yet, almost every day, we learn some new things that are really exciting and cool

And we get questions. Lots of questions.

A question we get a lot around here is about the "water-softening capability of botanicals", to which I respond almost reflexively, "There is none." Botanicals will not help you soften hard water.

I believe that anyone who tells you this categorically simply does not have the correct facts. Ask them to explain how this process occurs. I'd like to know, 'cause I've found no evidence of this! 

Hobbyists really want an inexpensive, "natural", or simple way too soften their water. Using some botanical-based stuff just seems so right, doesn't?

Well, we also get a ton of questions about peat moss...mainly, what it can do in aquariums, and why we don't carry it. 

We'll get to that part in a minute.

Let's talk about peat moss in general for a bit. There is a lot discussed about peat's ability to "condition" aquarium water. And, although some of the facts might a bit convoluted, there is some validity to this.

Yes, interestingly, it is known that our old and controversial friend, peat moss, has actually demonstrated some capacity to conduct ion exchange ( a process in which which unwanted dissolved ions in water are exchanged for other ions with a similar charge.) Ions are atoms or molecules containing a total number of electrons that are not equal to the total number of protons. (I know, if you're like me, that made your head start spinning almost instantaneously.😳

Think of it this way: Peat softens water by exchanging humic acids for magnesium and calcium.

It's actually true.

Peat effectively binds calcium and magnesium ions, while simultaneously releasing tannic and other acids into the water. These acids "work" the bicarbonates in the water, reducing the carbonate hardness and pH to some extent.

And it will tint the water, as we all know.

Interesting, right?

However, you can't just drop some peat into your tank and expect "Instant Amazon." This process requires "active peat filtration" (the water passing over over the peat itself) to make this happen. There's more to this, and we'll touch on that in a minute.


So, what doesn't Tannin offer this stuff?

Well, there is that ethical question about peat being an ecologically non-sustainable product. Now, for decades, aquarium hobbyists used peat moss for the purpose of lowering aquarium pH, creating "tinted" water, enriching planted substrates, and for spawning killies and other fishes. It's easy to use, comes in a few forms, and definitely "works as advertised" when it comes to aquarium use! 

Now, in all fairness to us, the bulk of the peat moss harvested worldwide is used in the horticulture field, and aquarium use likely accounts for the tiniest percentage of worldwide peat consumption. Nonetheless, its use for aquariums has been discouraged in recent years as we take on a more environmentally conscious, sustainability mindset. That's cool!

And I suppose, if it follows the sort of way the aquarium hobby is treated by the media and environmental groups when it comes to related issues, such as fish collection and such (just read up on the Hawaii fish collection ban for more on that stuff) . In general, we're the easiest target- the "low-hanging fruit", without any real significant  "lobby" or industry advocacy for this kind of stuff, so it's natural that we'd be a target.

And of course, we need to self-regulate a bit. And we largely do.

Okay, so, what exactly IS peat moss...and why the controversy about its use?

"Peat moss" is the collective name given to mosses from the genus Sphagnum, which contains almost 400 species!  Peat comes from bogs, which are one of the four main types of wetlands recognized by ecologists. It's generally decomposed moss that accumulates in these bogs, which is then commercially harvested. This material been used extensively in agriculture, because it excels at retaining water: Peat plants may hold 16–26 times as much water as their dry weight, depending on the species!

Over the years, there has been a lot written about the sustainability, or lack thereof- of harvesting peat moss. It's sort of a "poster child" for the management of precious natural resources, and there are environmental consequences to removing this material from the bogs where it accumulates.

(Image by Boreal. Used under CC-BY SA 3.0)

It's been estimated by scientists that peatlands store a third of the world's soil carbon, and their harvesting and use releases carbon dioxide, the major greenhouse gas driving climate change.


Although degraded peat deposits have often been restored by blocking water drainage sources, throwing in Sphagnum seeds, and covering them with a water-retaining mulch, it's not that simple a story. Yes, restoring peatlands does help soils by improving water-holding capability; however, the bacterial respiration caused by the decomposition of the mulch and other organics in the restored deposits continues to release C02.

According to some studies, it can take several years for the photosynthetic rate of the new peat deposit to beat the "respiratory rate", meaning that there is a net loss of carbon into the atmosphere during this period of time, which unfortunately contributes to the production of greenhouse gasses. 

(Photo by Ed Blodnick)

Now, there are two sides to every story, and there are a lot of great efforts being made to harvest peat in what most would agree to be a sustainable manner. Canada supplies up to 80% of the peat moss consumed in North America, and the peat industry there has put in significant effort to create what they feel is a sustainable resource.

According to industry studies, Canada contains 294 million acres- or approximately 25% of the entire world’s peatlands! The Canadian horticultural peat industry operates on less than 55,000 acres of these peat bogs nationwide. According to the industry, the amount of peat moss harvested from Canadian peat bogs every year is nearly 60 times less than the total annual accumulation of new peat moss.

That sure sounds like they're doing something right, doesn't it?

I think so! 

Being good stewards of a precious resource like tropical fishes, we can appreciate efforts made to conduct business in a manner that respects the environment.

So where does that leave us? 

Well, to be quite honest, I go back and forth. I told myself for a long time that if Tannin offered peat products, they'd definitely be from Canadian sources, because the industry there makes a significant overall effort to manage the peatlands.

Okay, we've kind of covered the ethics here, and we have sort of validated the hobby's "worst-kept-secret" that peat can soften water.

However, is it efficient?

Um, not in my humble opinion.

Being the curious, and occasionally reckless fish geek that I am, I played around with this idea once, to try to see if this does, indeed work.

And, well, it does sort of work.

It took a shitload of peat and a fair amount of time to reduce my Los Angeles tap water, with hardness exceeding ~240ppm and ph of 8.4 down to "workable parameters" of 6.4ph and a hardness level of around 40ppm. How much are we talking? It took a full  2-cubic-foot bag of peat, added to  a 30-gallon plastic trash can, filled with with my tap water, over 8 days in order to achieve these parameters.

So, yeah. The idea does work. However....

By comparison, my SpectraPure 4 stage RO/DI unit cranks out 80+ gallons of zero TDS, zero carbonate hardness water in a day. Now, one could argue that the rejection rate of RO/DI makes it less efficient- but hell, I water my garden with the reject water! And yeah, a unit like mine retails for around $300 plus USD, more than a 2-cubic foot bag of peat, but the long-term, consistent efficiency, ecological "friendliness", and reliability is pretty obvious to me. 

All in all, for maximum efficiency, consistency, and control, just invest in an RO/DI unit and you'll create soft water with little effort and no mess.

Yeah, it IS a bit pricy to purchase an RO/DI unit, but well worth it, IMHO.

But yes, you CAN soften water with peat to some extent if you're put to it, have the means to do it, and test. I've long ago lost that thrill that some people get from these types of "money-saving DIY" methods. To me, I simply decided to forgo other indulgences, save my money for a while, and invest in  the RO/DI unit and call it a day.

You should, too.

Are there alternatives to peat moss?

Well, sure.

However, they don't offer some of the "capabilities" (ie; the ion-exchange thing") as peat, but they do tint the water, impart some tannins and humic substances into water, and offer similar soil/substrate-enhancing properties. For example, our "Fundo Tropical" and "Substrato Fino"  are coconut-based, and are derived from the processing of coconuts for other uses.

Since most coconut harvesting is done by hand, large-scale use of fula-guzzling, exhaust-emitting tractors and such is limited. And growing coconuts doesn't require pesticides or herbicides. And our coconut-based products come from smaller, family-owned operations, not large commercial farms which often raze coastal mangrove thickets in order to grow more coconuts, and have little regard for that precious ecosystem. 

It's not perfect, but the environmental impact of both of these products is substantially and demonstrably better, in my opinion, than peat. ("Yeah, but if they're shipped via airplane or deisel-fueled boat or truck..?" Okay, right...but we're talking about the production side here, so...😂 )

And of course, this discussion on sustainability dovetails nicely with the general discussion on botanicals in general. Like, how sustainable is the selection of stuff we offer?

It's not perfect. We're trying, though.

I spent quite a few years developing direct contacts with the producers of the botanical materials that we offer. Most of these suppliers are family-owned businesses in areas like Southeast Asia or India. These businesses generally grow the materials for other purposes, like fruit production, furniture manufacturing, etc. Much of the material is a sort of "by-product" from other uses.

Many of these operations are not just gathering materials from wild habitats; rather, they are harvested by hand from their own farms and land. And what's really cool is that, once you're "in" with these people, they'll often refer you to their friends or extended family who do similar work. These referrals have led to us developing some of our most trusted suppliers for cool stuff. And it's good for them, too, providing income and employment for the local communities.

The ones which collect stuff from the wild are generally doing this with proper supervision/permits on government-managed forest lands, or under the auspices of local agricultural/ ecological authorities and programs. I've dropped a few suppliers and products because I was pretty certain that they were not procured in a sound manner.

I'll continue to do this.

Yes, it will result in the disappearance of some products from our lineup temporarily, or even permanently, but it's important for us to do our part when we can.

Of course, it's not a perfect system.

Even though our supplies are often more limited than we'd like, more expensive than stuff offered by upstart competitors, and can be subject to disruption for a variety of reasons, we've always felt it best to do business this way, as opposed to hitting up large importers of stuff intended for other uses (construction, home decor, etc.), like many of our erstwhile competitors do. In addition to being of questionably sustainable origin, some of this stuff is treated with varnishes and preservatives (because it's intended for other uses), which would have deadly consequences for fishes in aquariums.( I know, because we test and use everything that we sell, and we've been burned in the past!)

Yeah, it's tedious and pricy at times. We pay more for our stuff, which, unfortunately, is reflected in our retail pricing. Yet, I think over the past 6 years we've done things pretty well. Not absolutely flawlessly, but pretty damn well!

I'm okay doing business this way. Again, it's far from perfect, shockingly inefficient  at times, and there are still some efforts I'd like to see being made by some of our suppliers to be even more ecologically friendly.

However, supporting these small, often family-owned operations has been a much more gratifying approach for many reasons. They tend to be more responsive to our customers' needs, resourceful at what they do, and it's nice to know that our dollars (and yours) go into the hands of these businesses directly, supporting their livelihoods and that of their employees. And, being on a first-name basis with the owners is very cool! It's really been fun actually FaceTiming some of these people while they're processing/harvesting/gathering the very materials they're getting together for us! 

We'll keep refining this process, even if it means eliminating a substantial portion of our offerings over time as we source more sustainable/ethical substitutes. We'll keep looking for viable alternatives and innovative offerings whenever we can. 

So, back to the "peat thing." 

I don't think that we're likely to be offering peat any time soon. Again, there are some sustainable operations out there. However, we just feel that this is a product which most hobbyists can procure themselves, or use the many cool alternatives available. There are just too many ethical considerations that we believe are best addressed by the individual.

It's neat stuff. Amazing stuff, actually. It works "as advertised", but the "baggage" that it carries with it seems a bit too "heavy" for us to want to contend with.

Besides, there are so many other interesting things for us to play with in our botanical world; we'd best spend our time looking for and creating some new and exciting things.

It's what we do.

It's what will keep moving the hobby forward.

And it's what you expect from us!

Glad to have you along for the ride.

Stay thoughtful. Stay creative. Stay curious. Stay bold. Stay innovative...

And Stay Wet.


Scott Fellman

Tannin Aquatics 





Scott Fellman
Scott Fellman


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