Where do your seaweeds come from?

Everything seems to have been well written about aquarium algae!

"Reading some forums or social networks, one might even believe that fishkeeping is primarily about fighting against algae. Filamentous algae, brush algae, green water, or even cyanobacteria, which are a primitive form... We all tear our hair out to banish these diabolical beings from our aquariums and ponds, usually with at best a temporary result, almost always nonexistent."

A researcher friend once told me, while I was asking him about the moss that was taking over my lawn: "The only effective way to get rid of the moss problem is to stop seeing it as a problem. That's the only thing that works."

He explained to me that someone who thinks that we need to eradicate foxes to save our chickens should ask themselves why they hate nature so much, wanting to eradicate it rather than adapt to it.

How do algae get into our aquariums?

"Is it by introducing a plant that carries it? They all carry it, except for in vitro plants that live in a sterile bubble! And they even need it to live, as it is part of their microbiome. Plants are covered with hundreds of species of bacteria, viruses, algae, various microbes and could not live normally without it."

"You have to choose: either the sterile environment or the open environment."

The sterile environment is a mirage. Even laboratories would be unable to conceive and maintain it sustainably.

"So, you will tell me, let's at least try not to introduce too many algae by carefully cleaning everything that goes into the aquarium!"

Look at this young tree, which has been pruned.
"See how green the cup is. They are essentially algae. They are not very present on the bark, but they have been well nourished on the pruning wound. No relation to the fact that the bark has not received any."

Oh yes, the algae are everywhere, and no one inoculated these algae on this tree. They came on their own, with the air and the dust. Millions of spores.

It is now known that in a single gram of soil taken from the surface, there are several hundred different species of algae! This was unknown, but high-throughput DNA sequencing has recently revealed it. We know less than 5% of these species! Their spores are carried by the wind and are everywhere in the air, by the millions.

Our aquariums, unless they are hermetically sealed and therefore sterile, are also seeded every day by the ambient air with at least dozens of species of algae. Life is everywhere, and it is much stronger than our dreams of control!

Wanting to avoid introducing algae is futile. Even tap water contains some. Not much, but still a little.

Fill a bottle with this water that you believe to be lifeless, close it and put it in the sun: you will soon or later see cyanobacteria, unicellular algae in suspension (green water) and soon perhaps filamentous ones!

And if that were therefore normal?

And if algae served a purpose?

"While it is futile to want none, we can, on the other hand, limit them by favoring fast-growing plants. Elodea, Egeria najas, the hornwort, vallisneria, and many others deprive algae of food as they are so greedy."

"Do not use any fertilizer: these plants consume resources and slow their growth when water has become scarce. That's good: algae are in short supply!"

Personally, I have gotten into the habit of occasionally removing filamentous algae or various cladophora by hand. It’s pleasant to do, quick, natural, and much less time-consuming and messy than changing your filter every month!

"Avoid algicides at all costs. Removing the problem by killing the algae will only upset the balance, shift the problem, and especially introduce a toxic biocide molecule."

Tolerate, limit, observe, wait.
"With nature, only compromise works sustainably."

Your fish, they don't care.
Your snails are feasting on it.
Your microfauna and your fry hide there.

Are your plants not healthy?
So think of the young tree in the photo, the old tree covered in lichen, and even your skin covered with a microbiome (including many mites!) that it could not do without.

Life is superb in its complexity. It is everywhere.

"Let us tend to our aquariums like the wise man tends to his garden: without intransigence."