Greg's Corner Archive November 2024 - Brushing up on Biofilm

This article was fun. I've added commentary at the end to clarify a few points that I've since learned in the research phase of bio-Boost: Foundation. Rabbit holes are always fun to dive down, and they really open up your view of things.

 

Greg's Corner November 2024: Brushing up on Biofilm

It's been a while since I’ve done an article and I do apologise but personal circumstances have kept me busy. So to make it up to you, this month's Greg's Corner is all about Biofilm. (And it gets pretty in depth, so buckle up and grab a coffee).

 

What the hey is Biofilm, who in the what is Aufwuchs, and why do I feel like that's just a rude phrase?

Okay, well… Biofilm is defined as colonial bacteria or other microscopic organisms that feed off the sugars of botanical components in the water column. It can also be used to describe and define the other organisms that predate on that bacteria or otherwise utilise the film produced as either food or shelter.

 

Aufwuchs (gesundheit) [pronounced ORF-VOOKs {like books}] can be defined as the microflora and fauna (tiny microscopic critters) adhering to parts of rooted aquatic plants and other open surfaces, also organisms and detritus coating rocks and plants in an aquatic environment often fed on by grazing fish.

 

Also called Periphyton in Aquaculture and marine biology circles.

 

Biofilm can have a few different looks depending on a number of factors.

 

 

 

It can look like green walls:

 

 

 

 

 

 

 

 

 

 

 

 

Or gross white (and heckin’ stinky) slime:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Or mulm build up on the hardscape/aquarium floor:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

So why is Aufwuchs/Biofilm/Periphyton so important?

For several reasons. First and foremost, the microflora and fauna that form the film provide a fantastic indicator of water quality. It is common knowledge among seasoned aquarium hobbyists that the presence of Aufwuchs in large amounts indicates that an aquarium has cycled adequately and is beginning to mature.

It also provides a rich food source for grazing organisms like snails, shrimp and catfish. Even certain cichlids like the so-called Mbuna Cichlids of Lake Malawi (specifically

Labeotropheus trewavasae and Pseudotropheus zebra) have developed rasping teeth that they use to scrape Aufwuchs from rocks for consumption.

 

It's also important to note that certain beneficial organisms that can be found within Biofilm are known to release chemical compounds called "Allelochemicals" that inhibit the growth of harmful organisms like cyanobacteria. (Wu et al., 2011).

From <https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/periphyton>

 

Biofilm also plays a heavy part in waste/mulm disposal. bacillus subtilis is one of the more common "probiotic" bacteria found in waterways and used heavily in septic and sewage systems. It is very effective at breaking down organic matter into less nasty mulm. This is super important in heavily planted tanks where siphoning out fish waste is impractical. A healthy presence of such bacteria significantly reduces the amount of cleaning necessary to keep your tank in tip-top shape.

 

Many of these bacterium are also used within your wet pet's Gastrointestinal tract as well. In the gut they provide protection against toxins and hostile bacteria in addition to aiding in digestion of complex proteins and carbohydrates.

 

As it turns out, bacteria like b.subtilis are actually beneficial for plant life as well, providing enhanced tolerance against stress and protection against bad bacteria and fungi.

 These benefits are obvious and proven by Marine Biologists (as well as terrestrial biologists, including Agriculture specialists. Interestingly, Aquaculture companies have also done extensive research into the benefits of bacteria in their systems). Biofilm is a very important component of aquatic environments and should not be dismissed simply because it looks unappealing.

 

 

Enough Science. Tell me how to grow this stuff.

Alright, alright dear reader. I'll stop with the boring science. (But on the off chance you want to learn more science-y stuff, feel free to write me via email or social media or harass me in person at the next SKV or ASoV meeting.)

 

Well sadly, there's still a bit of science involved. But I'll try to keep it simple, I promise.

 

To generate adequate biofilm in a fresh aquarium from scratch can take 6 months or more. Once the tank is cycled, you must leave it running and let nature do its thing. Fortunately, there's a crap-tonne of ways you can cheat this process.

 It should be noted that pretty much all of the Beneficial Bacteria in your aquarium are Aerobic - which means they need oxygen to function. So make sure you have adequate water circulation/gas exchange or you'll run into a spot of bother.

 

You'll also benefit from having botanicals in your aquarium for the biofilm to feed on - this can be anything from driftwood to leaf litter to lubao balls (I'll do a seperate article on these in the future - I've got a similar product launching early next year so I'll have plenty of trade secrets to share).

 

Begin by using pre-seeded filter media. You can use some from an existing tank, or beg/borrow/steal (my editor informs me I'm not allowed to use that phrase. My apologies) some from a fellow fish keeper or your local aquarium.  I personally keep extra bio-media in a canister filter on one of my 3ft tanks for this purpose. You can also use pre-established driftwood from a tank that's full of biofilm to kickstart this process but it will still take a month or two. The process is slow. But if you're made of money (or just really really impatient) you can purchase products like Glasgarten's Bacter AE (extremely concentrated, and only contains bacillus subtilis and prebiotics) or my own bio-Boost: Foundation (available for trial in Jan 2025) which will superboost the process and bring your biofilm growth time down to 2 weeks (or less. Or more. It's not an exact science, and a number of factors can affect the growth rate of bacteria). These additives work this miracle because they contain freeze-dried bacteria and bacterial food just ready to be activated and go to work - Just add water!

 

Do I need biofilm in my tank?

Not necessarily, but you'll definitely benefit if you have grazing species like plecos, otocinclus, snails or shrimp in your tank. Through past experience (read: several years of trial and error) I have found that grazing species tend to breed more often when plenty of food is present and babies also tend to have a higher survival rate. It is my firm opinion that an abundance of biofilm triggers certain instincts in shrimp and catfish that simply spot feeding may not do. For example, I had a colony of 20 Blue Dream Cherry Shrimp in a tank for 2 years and they never bred once. I moved them to a tank with a heavy biofilm presence (green walls, mulm on the floor and all the works) and within 2 weeks, every single female was egg laden. Note that the water parameters (pH, GH, KH, Temperature) were all nearly identical. I had a similar experience with my Crystal Red Caridinas. Only one female at a time was having offspring until I moved them to a properly set up tank. Not quite a month later, I discovered that nearly all my mature females were carrying eggs.

 

Other seasoned breeders including Con McIvor and many of the high grade Asian breeders also swear by having Green Walls and biofilm. It certainly seems to work and as a friend of mine once said: "If it works, do more of it".

 

 

 "Aufwuchs" refers to the larger (but still microscopic) organisms that use Biofilm… what are they?

 

Well, that's an interesting question.

 On top of the various (and too numerous to name) bacteria, yeasts and molds that live in biofilm, you have larger micro-organisms like Ostracods and detritus worms that feed on the film, and are often popular food for fish. Daphnia and bloodworms can also make use of biofilm as a food source, as can snails and other crustaceans. I could keep name dropping common live fish foods but for the sake of saving the trees, I'll stop now.

 

Suffice to say, biofilm plays what can be argued as the most important role in aquatic ecosystems. From the large and hungry fish at the top of the food chain right down to the teeny-tiny critters not visible to the naked eye - everything benefits from healthy biofilm.

 

My dear sister Tracy - the woman that got me involved with this hobby nearly two decades ago - always used to say "your fish tank must be as alive as the fish you put in it"... and boy was she right.

 

 This has been a pretty in-depth topic to cover. I’ve tried to simplify it as much as possible, but some things may not have come across correctly or may have been left out for the sake of space and simplicity. If you've got any questions about this article or want any further info regarding any of the topics covered in this article please reach out to me. I'm at most ASV meetings, all SKV meetings and you can contact me by any of the following methods:

 

E: gregory@niskai-aquatics.com

F: facebook.com/niskaiaquatics

I: @niskaiaquatics

 

If you’ve stuck around for the whole six pages, have a cookie. And please do come chat with me about how cool al this biology stuff is. I really can talk your ear off for hours about it.

But for now, Adios and see you at the next meeting!

 

Updates with more improved knowledge:
So the cool thing about biofilm is that is comprised of a number of biopolymers secreted by bacteria. Biofilm is also present in terrestrial soil - that rich loam that we all love for our gardens is kept moist and clumpy by the biofilm present. 

Other cool notes: the majority of bacteria we love to cultivate in our aquariums are identical to those used in agriculture. Bacteria live within the moisture in the soil, and function pretty much the same in dirt or water.