Should one clean their aquarium?

Should an aquarium be "clean"?

And what does that mean?

 

"When I was young, a lady told me that her son was a passionate and highly experienced aquarist. And to illustrate the care he put into his passion, she proudly explained to me that he 'never put his hands in the water,' as an aquarium is so fragile and very technical."

It was a time when microbes were concerning and the response was to eliminate them.

Of course, we knew that the aquarium filter contained bacteria.

A filter is what ensures the hygiene of the aquarium.

He has two functions.

 

One is mechanical: it sucks in and retains all the "impurities" suspended in the water.

The other is biological: it hosts the bacteria that break down these wastes, transforming them into nitrites and then into nitrates, which are less toxic and consumable by plants.

"So, in the absence of plants to consume them, the filter produces nitrates that accumulate in the aquarium. It NEVER makes them disappear."

But above all, we now know that, in the absence of a filter, the same bacteria do exactly the same work, but in the aquarium itself. Simply.

 

So, if there is no filter, impurities (droppings, dead leaves, forgotten food...) settle at the bottom and the bacteria, the same as in a filter, take care of degrading them in the same way. They are present in the sand, on the glass, on the plants and rocks, and even suspended in the water!

 

The only difference is therefore purely aesthetic: without a filter, there are a bit more visible deposits on the bottom, knowing that no filter sucks them all up anyway.

So, whether filtered or not, if we don't like the natural appearance of these deposits, we occasionally use a "vacuum cleaner" that siphons all of that in just a few minutes.

Since this observation of the very modest (if not negligible) usefulness of the filter for the balance of an aquarium, knowledge has only advanced on microbiomes (the collections of microbes present in the same system).

We now know that the most diverse microbiomes are the most stable. Where we used to buy a small handful of bacterial strains to ensure the famous nitrogen cycle, we now know that this cycle is maintained by hundreds of species, and the same goes for many other cycles (phosphorus, potassium, etc.).

"In the same way that many modern diseases are caused by a depletion of our gut microbiota, an aquarium is all the more stable when it contains a high number of microbial species."

 

The more different species there are, the less room there is for a new arrival that would want to invade everything, for example a pathogenic species.

In a complex microbiome, everyone keeps their distance!

"This is how veterinary medicine has theorized the astonishing concept of 'clean dirt'."

"It is no longer a question, in farms, of sterilizing everything, of seeking a perfectly vain total asepsis. On the contrary, such an 'extreme cleanliness' would give any new microbe coming from the outside free rein to proliferate, encountering no competition."

"We now prefer a strategy that involves tolerating a certain residual 'dirt', which actually contains all the microbes that farm animals are accustomed to, as they are their own. Their defenses are adapted to it, and their bodies live with it."

 

"It is for this same reason that, when you travel, you dread 'turista'. It is not necessarily due to a lack of hygiene in the country, but mainly because the microbial strains present there are unknown to your body, which therefore does not know how to cope with them. If you live longer in that same country, you will no longer have 'turista'."

 

A tank that is too clean is generally unstable.
No natural ecosystem is sterile. On the contrary, all surfaces in nature are covered with microbes (our skin, our intestines, the roots of plants, a simple pebble, a grain of sand...).

 

It is estimated today that the proportion of pathogenic microbes is less than 0.5%, even among the viruses that scare us so much.

The skin of a fish, its mouth, its digestive tract, etc. are made to live covered in microbes.
Even plants live completely covered with bacteria, viruses, and even micro-algae, some of which are essential for their health or for the absorption of certain elements by the leaves. An aquatic plant without algae does not exist in nature.

A small daphnia , a nice Blackworm, a bladder snail or a water louse, when they make a simple poop, each releases several thousand different microbial strains (between 4 and 10,000) into the environment.

And the aselle does not produce the same as the daphnia , which also does not produce the same as a ramshorn snail!

 

True biodiversity is actually microbial.
And natural aquaristics, which relies on this biodiversity, uses it instead of fighting it.

Microfauna, microbes or algae, nothing really scares it.

A natural aquarium is therefore rather "dirty", but it is proud of it!