Aquarium after the renovation, how is it doing and what changes have occurred? The first photo is right after the renovation and the second one is after 1 month and 17 days. What do you think? Would you change anything?

On the banks of the Vistula, a system operates that would have seemed more like an experiment than a part of urban infrastructure just a few years ago. Warsaw utilizes freshwater mussels as living sensors for water quality. This is not a curiosity, but a full-fledged layer of protection for drinking water, directly connected to the control systems of the waterworks.

The basic principle is simple: mussels filter water, and if something harmful appears in it, they immediately close their shells. This movement, which is a matter of survival for the organism, is translated into data in Warsaw using sensors attached to their shells. The system monitors group behavior and responds to synchronous changes.

Technical Solution

Small sensors are attached to the shells, measuring their opening in real-time. Data is continuously evaluated and filtered to eliminate random behavior of individual organisms, thus the behavior of the entire group is closely monitored. Once multiple mussels begin to close simultaneously within a defined time frame, the algorithm evaluates this as an anomaly and responds by issuing an alarm. This signal is connected to the waterworks control system (SCADA), which can automatically react—such as by shutting off the water supply.

The technical implementation is simple yet precise. Small sensors are attached to both halves of the mussel, capable of measuring the distance between them with high accuracy, that is, the degree of opening. Data is transmitted to the control unit at short intervals, where it is processed. Importantly, the system does not work with a single immediate impulse. It first filters out random movements and the natural behavior of individual organisms, then tracks trends over time, and primarily compares reactions among multiple mussels.

Mussels Discover More Than Classic Sensors

Unlike traditional probes that measure specific parameters such as pH, conductivity, or the presence of defined chemical substances, mussels operate differently. They respond to the overall impact of the environment on a living organism. This means they can detect situations where an unknown substance or a combination of multiple factors appears in the water, which individually might not exceed any limits from the sensors' perspective.

In the case of contamination, mussels close within seconds, and the entire system can evaluate the situation within tens of seconds to one minute. This speed makes biomonitoring an ideal "first warning layer" that complements more detailed but slower laboratory analyses.

To maintain reliability, the system works with a group of several individuals, and their behavior is continuously calibrated. Mussels are placed in a flow chamber, where they constantly filter water from the river, and after a certain period, they are replaced to prevent adaptation to the environment.

The great thing about this is that the mussels are not harmed; they live in an environment similar to their natural habitat and are returned to nature after a few months, with their place taken by their successors.

This is what aquaristics can look like in a country where theft is practically nonexistent and rules are followed. In a residential area, there is this open aquaristics where you can choose fish or accessories and pay into a donation box.

Official Announcement of the National Exhibition of Aquarium Fish, Reptiles, and Skills

Open Championship of the Czech Republic in Breeding Livebearers (Guppy, Xipho, and Molly) – Czech Open
Following the championship exhibitions organized by the former association Akvárium, established in 1899.

Organizer: AQUARIO & spol. n.o., ID: 27016439 | aquario@aquario-euro.net

Member of IKGH – International Kuratorium Guppy High-breeding
Václav Schebelle – Associate judge for clubs for the 2026 European Championship season
Held as part of the exhibition EXOTIKA 2026
Date: October 28 to November 1, 2026 (Wednesday to Sunday)

Program 2026:
- Competitive Exhibition: Championship of the Czech Republic in Breeding Guppy, Xipho, and Molly.
- Natural Biotopes: Exhibition display – Central America, Amazon, Africa, Asia.
- Aquascaping: Exhibition of "aqua players" (tanks 0–200 l).
- Aquarium Free: Open competition creation and presentation by aquarists (tanks over 200 l).
- Marine Aquariums: Exhibition display (octopuses, seahorses, corals, etc.).
- Snails and Beetles: Bred forms from Africa.
- Orchid: Thematic flower exhibition.
- Antiquarian: Specialized literature from the relevant fields.
- Lectures: Marine aquaristics, genetics, invasive species + GMOs, Czech aquarium pond, and more.

Details of the Exhibitions:
Championship Exhibition: Conducted according to the global regulations of IKGH.

Guppy: collection of 3 males + 1 female, or pairs (male + female). Evaluated on consistent traits (fin shape, color, size, vitality).
Xipho and Molly: always a pair with consistent traits.
Biotope Exhibits: A glimpse into pure nature without artificial decorations and visible technology.
RETRO Exhibition: A reminder of the beginnings of aquaristics in Europe.
Aquascaping: A modern style of aquaristics emphasizing the harmony of plants, light, and decorations.
Snails and Beetles: Exhibition and sales display (African snails, terrestrial crustaceans – "pigs," etc.).

The exhibitions will showcase both natural and highly bred forms. The event will include the sale of fish from domestic breeders and the distribution of the AQUA directory (contacts for breeders of specific species).

NEW: Open Amateur Exhibition with Sales
We invite all hobby aquarists to showcase their breeding strains of GUPPY, XIPHO, and MOLLY to the wider public. Separate tanks will be prepared for registered participants (smaller exhibition tanks and larger sales tanks).

We encourage all aquarists and clubs to participate! Come compare your breeding successes and experience the prestigious atmosphere of the championship.

Further organizational information will follow, or we will provide it in person.

On behalf of AQUARIO & spol.

Václav Schebelle

The first photo is before the edit and the second one is after the edit. Which one do you like more? And what would you change or add, if anything?

Máte plný kalendář, ale o té nejlepší burze nebo přednášce se dozvíte až den poté? Německé Cichliden-Forum.de pořádá online přednášku, která potěší každého, kdo chce mít o dění ve světě akvaristiky dokonalý přehled.

Online přednáška: Vivaristik-Kalender v praxi
Manfred Dietz představí revoluční nástroj pro všechny akvaristy – Vivaristik-Kalender.

Kdy: středa 8. 4. 2026 v 19:30

Kde: Online (Zoom)

Jazyk: Němčina s českými titulky v reálném čase (přes 40 jazyků k dispozici)

O čem to bude?
Cílem je sjednotit všechny termíny, akce, odkazy a místa na jedno místo v cloudu. Manfred vám ukáže:

✅ Jak najít všechny akvaristické akce na jedno kliknutí.

✅ Jak předcházet nešťastným termínovým kolizím.

✅ Jak si kalendář propojit s vaším vlastním telefonem nebo aplikacemi.

✅ Praktické ukázky přímo v rozhraní kalendáře.

Na konci přednášky bude vyhrazen dostatek času pro vaše dotazy a pomoc s nastavením.

Proč se připojit?
Vivaristika není jen o rybách v akváriu, ale i o setkávání a sdílení zkušeností. Tento kalendář je mostem, který nás všechny propojuje. Hosté jsou srdečně vítáni!

Tip pro české akvaristy: Díky funkci Zoomu budou k dispozici automatické české titulky, takže se nemusíte bát jazykové bariéry.

Chcete se zúčastnit?
Sledujte web Cichliden-Forum.de pro získání přístupového odkazu k Zoomu.

An Zoom-Meeting teilnehmen:

https://us02web.zoom.us/j/82319496616?pwd=LjA2oPUsfVaOxub63B32TB3wDvGuji.1

Meeting-ID: 823 1949 6616

Kenncode: 020589

Scriptaphyosemion schmitti are beautiful lampeye killifish. My Schmitti stand out best in a dark environment. Their metallic blue and red colors literally shine when the aquarium is dim. The fish have fallen in love with the moss and enjoy resting in it. I maintain the temperature around 22°C and pH 6.8. They love to feast on Izya worms and daphnia. However, they are not very keen on Tubifex, which surprised me quite a bit. They would rather indulge in dried food instead.

While traveling in Japan, I came across fish farming in the city of Beppu, famous for its hot springs. Unfortunately, the Japanese attitude towards animals is not ideal, and it shows... The arapaima looked completely desperate. 😤

While reading the fantastic book Ocean by David Attenborough, I came across an interesting creature that I would like to share with you.

Enypniastes eximia is a dark red deep-sea sea cucumber, unflatteringly referred to as the "headless chicken monster" due to its appearance while hovering above the sea floor, although it is actually a beautiful creature. This species of sea cucumber (order Elasipodida, class Holothuroidea) is unique in that it can detach from the sea floor and "fly" in the water column. Enypniastes is a close relative of the well-known "sea cucumbers."

Enypniastes has a gelatinous, translucent body (often very transparent in younger individuals) and a wide "veil" at the front that functions as a swimming surface. It measures about 10 centimeters and its surface is sticky and stinging.

Most of the time, the sea cucumber spends on the bottom in a horizontal position, gathering food with its legs from the upper layer of sediment, but when it needs to change location quickly or escape, it hovers above the sea floor. A remarkable feature of Enypniastes is that when threatened, it can "shed" the outer layer of its surface and release it, drifting away in another direction.

Beautiful footage and many more interesting facts about this creature can be found in these videos:

https://www.youtube.com/watch?v=dJnbbt9QVtA
https://www.youtube.com/watch?v=YnR-Agj7crM

Zveme vás na další Akva Tera bazar který se bude konat v kulturním domě Delta v Břeclavi.

9 pieces of shrimp

Aqua Congress in Žďár nad Sázavou
Organized by the Tetra Aquarists Association

Date: Saturday, April 18, 2026
Speaker: Radim Blažek, Ph.D.

Program of the day
10:00 – Meeting of the AKVA CZ associations

13:00 – Afternoon lecture with Radim Blažek

16:30 – Announcement of a rich tombola

19:00 – Party with dancing and free entertainment

Lecture topics:
1) Pitfalls of fish and their parasites research across Africa
Peek behind the scenes of scientific expeditions into the heart of the African continent.
2) Cuckoos with fins
Unique feathered fish from Lake Tanganyika and their fascinating breeding strategies.

Volume 100 l, lighting Diversa led expert white, filter JK Atman pump with biomolitan, plants of the genus predominantly Vallisneria, Rotala, Lugwidia, Echinodorus, Bleher's/ocelot.. no fertilization, no CO2.. fish once Mikrogeophagus ramirezi, Loricaria catfish, various Ancistrus sp.. the aquarium was in operation for 3.5 years before it was discontinued.. during the 3 years there were a few changes... I wanted to show a simple way without using CO2 or any fertilizers.

Přání k Vánocům a na konci roku

Drazí čeští akvaristé,

rok 2025 se chýlí ke konci. Byl v mnoha ohledech jiný a náročnější, než jsme na začátku doufali. O to více nás těší, že se v tomto roce navázal velmi dobrý kontakt s vámi. Považujeme to za výjimečně pozitivní a cenný vývoj.

Jménem Cichliden-Forum.de, DCG e.V. a VDA AK-Fischkrankheiten vám srdečně děkujeme za konstruktivní a důvěryhodnou spolupráci. Velmi se těšíme na její pokračování i v příštím roce.

Rádi bychom také nezapomněli zmínit, že velké nasazení, mnoho nápadů a úsilí všech zúčastněných si zaslouží zvláštní pochvalu. Bez vašeho osobního přínosu by toto slibné partnerství nebylo možné.

Děkujeme všem českým akvaristům a mnoha dobrovolným pomocníkům za váš přínos v končícím roce 2025. Každý z vás se osobním nasazením podílel na zahájení a dalším rozvoji naší společné spolupráce.

Jsme pevně přesvědčeni, že i v roce 2026 upevníme naši pozici v akvaristice a naši započatou spolupráci určitě ještě rozšíříme.

Přejeme vám všem, vašim rodinám, blízkým a přátelům poklidné adventní období, veselé Vánoce a šťastný start do nového roku!

Ať vám přinese pár klidných dnů – čas na rozjímání, načerpání sil, být s rodinou a soustředit se na to podstatné.

Tyto dobré přání vám posíláme s srdečnými pozdravy

Manfred Dietz
jménem Cichliden-Forum.de, DCG e.V. a VDA AK-Fischkrankheiten

The Pantanal (swamp area) is half the size of Germany and the largest contiguous swamp area in the world. It is mostly located in Brazil, with the remaining parts in Paraguay and Bolivia. Since the year 2000, the Pantanal has been a UNESCO World Heritage Site and is protected.

It is home to numerous fish species, many of which are popular in aquaristics. The book about the fish of the Pantanal is unparalleled. Over 660 pages, the fish of this region are presented, with detailed text and an image that almost always shows the respective fish in live coloration. For each species, the morphological characteristics, live coloration, as well as information on occurrence, etymology, type locality, and economic significance are provided.

In addition to the mostly excellent fish images, there are also some habitat photos. A large number of authors were involved in the development. The book is printed in Portuguese. However, with appropriate translation tools, this should not be a problem.

NOTE: Portuguese text!

660 pages
PDF Digital
ISBN: 978 65-81066-05-5

Here is the link:
https://www.cichliden-forum.de/Mittel-Suedamerika/Montagem-livro-Peixes-VERSAO-FINAL-MARCO-2022-ISBN97865-81066-05-5-ONLINE_FINAL-1.pdf

Best regards,
Manfred

With the two volumes by Kai Qvist and Rune Evjeberg, you will receive extensive information and photos of freshwater biotopes and fish from the

rivers, lagoons, and cenotes of Mexico. The books are almost a must for those who are involved with Goodeidae, livebearers, cichlids, and
many other freshwater fish from Mexico or are interested in them.
Volumes 1 and 2 of "A Selection of Freshwater Fish Biotopes in Mexico" include 337 and 241 pages and are packed with detailed information about
the biotopes, water parameters, history of the fish, local communities, and much more.

Anyone with an account at https://de.scribd.com can download the two volumes there for free.

Here is the link to it:
https://de.scribd.com/document/47090…-Mexico-v-2-pdf

Best regards, Manfred

Hello everyone,

an interesting new release: "Handbook of Freshwater Fishes of West Asia"

The "Handbook of Freshwater Fishes of West Asia" provides the first summary of the taxonomy, distribution, habitats, and biology of all freshwater fish between the Bosporus, Azerbaijan, Yemen, and Iran. The region is extremely diverse and is home to 625 species, most of which are endemic.

Many of the species are known to only a few specialists, and the authors have spent 18 years compiling the information provided.

The book not only showcases all species in color photographs, the first site-specific distribution maps, and the current IUCN conservation status of all species. It also allows for their identification using identification keys and detailed diagnoses, points to many open questions for future research, and includes 1,142 references for further information. It unites the relevant and authoritative information necessary for understanding and researching freshwater biodiversity in the region and far beyond, and will serve as a standard work and timeline for many years to come.

all species in color photographs
distribution maps
current IUCN conservation status of all species
identification of fish using identification keys and detailed diagnoses

Citation
Freyhof, Jörg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash and Kaya, Cüneyt. Handbook of Freshwater Fishes of West Asia, De Gruyter, 2025.
https://doi.org/10.1515/9783111677811

Place of publication: Berlin/Boston
Language: English
Dimensions: 210 x 280 mm
ISBN-10: 3-11-167764-8 / 3111677648
ISBN-13: 978-3-11-167764-4 / 9783111677644

Download eBook (PDF 262 MB):
https://www.degruyterbrill.com/document/doi/10.1515/9783111677811/pdf?licenseType=open-access

Best regards to all,
Manfred

Warning: Contains old, ancient emigrants from the South of America, representatives of the genus Corydoras.. (female sterbai, female panda, male paleatus).. And African plants Anubias (where to put the nice surplus? 🤭..) They live there only to the end of their days and grow only in a stopover☝️.. So take the subcategory "biotope" with a grain of salt🫠..

The main inhabitant is the male Channa bleheri (somehow turned brown after two years, so probably the brown form), bred by Kuba Lasota, Heiko. Snails Planorbids, Lymnaeids, one lost Clithon, lost and rediscovered Melanoides, Filopaludina..

It is still a low-tech aquarium, where the only technology includes a pumping head from jk animals and an LED tube hsbao retrofit. Occasionally a skimmer jingye, for emergencies when one doesn't want to use tweezers.. But I don't want to get rid of it completely (is that possible?), I make jichu for watering houseplants 😁.. We fertilize with fish waste and maximum long-term NPK fertilizer in the substrate. The used leachate is literally alchemy. The base is Kachu, leaves of Quercus robur, Fagus, Schima, alder cones and leaves, Sphagnum, torf, lotus petals, lotus fruit.... The representatives of the plants growing here are Microsorum, Cryptocoryne, Bolbitis, Najas, Limnophila, Schismatoglottis, my favorite and simultaneously hated Lotus tiger, sometimes red, sometimes green, as it pleases (can be seen in the photo in my gallery, so I'm not making it up..), which was obtained by Jirka Fojtik from Surpan and from whom I also have Schismatoglottis (thanks!), Limna, Rhygoriza (I have it again after 5 years, thanks to Míla Popelka 🍀), and somewhere among all this are still living, just somehow leafless stems of Hydrocotyle leucocephala 😅... And finally, Java and hybrid mosses, Cladophora and Rhizoclonium, which didn't want to grow for a long time .. 👌.. And the lighting conditions themselves? Terrible... But it's growing! 😂

After about half a year, I planted new plants…

Profile: Exochochromis anagenys (Oliver, 1989)
Size of males: approx. 25-30 cm
Size of females: approx. 20-25 cm

Coloration, Differences:
Males and females are almost equally colored.
Gold yellow with three black spots on both sides.
Males grow significantly larger. With large yellow egg spots on the anal fin and bluish head.
As juveniles, the sexes are very difficult to distinguish.

Minimum tank size:
from 250 x 70 x 50cm, from 1,000l

Diet:
Predator, primarily feeds on juvenile fish that it actively hunts.
In the aquarium, they accept flakes, granules, frozen, and live food.

Habitat in Lake Malawi:
The species is widely distributed throughout the lake and hunts over sandy areas and rocks for juvenile fish.

Reproduction:
Maternal mouthbrooder

My experiences with Exochochromis anagenys (Oliver, 1989)

Keeping in the aquarium:
This species is one of my favorite species from Lake Malawi.
Since these fish are quite large and very active swimmers and must be kept in a harem, the aquarium must have a minimum size of approx. 250 x 70 x 60 cm (approx. >=1,000l).
The tank can be designed as a Malawi transition zone. Larger open sandy areas with rocks or rock piles placed in between. The species requires a larger free swimming space in the tank.
The animals are fish predators, hunting and eating smaller fish in the lake. The offspring of other species in the tank are therefore at least endangered!

The species is best kept as a harem of 1M / 3F. In larger aquariums, larger groups of the animals also work.

Diet in the aquarium:
The fish eat juvenile fish that they actively hunt in the lake. Therefore, a carnivorous, protein-rich diet for the animals is necessary. They accept flakes and granule food. Frozen and live food can also be given occasionally.
Please feed sparingly and with high-quality food (low carbohydrates).

Behavior in the aquarium (my experiences):
The species, where females and males look very similar, is a rather calmer Malawi predator in the aquarium, that gets along well with other species and is not aggressive. During courtship, it digs a small sand pit, usually under or next to a large rock. Here, the behavior of the male changes. The calm hunter becomes a somewhat rough character, which defends a minimum of 200 cm length in the aquarium fiercely. Moreover, he hunts his females very persistently, intensely, and until they are ready to lay eggs and swim into his pit. The courtship and hunting can last several days.
I have been able to obtain about 50 juvenile fish per brood several times, raise them, and give them away. The loss was very low, only about 3-5 juvenile fish on average.
The females brood for about 4 weeks and then release the fry at about 10-12 mm in size. The little ones are not further cared for and are left to fend for themselves from the first day after being released.

The fish are gold yellow in color and have three black spots on the left and right sides, which they can completely hide depending on their mood, making them entirely gold yellow. The dominant male also becomes bluish on the head, which then transitions into gold yellow. In my opinion, they are extremely beautiful and elegant fish.

Co-habitation in the aquarium:
A stocking with larger, not too sensitive fish must be chosen in the tank. However, the other fish should not be too rough and aggressive.
The species is, like many Malawi predators, quite a big "sensitive" fish, and they do not like changes in stocking, setup, or constant attacks from rougher other fish, reacting quickly with stress and taking it badly. This can possibly lead to diseases if it becomes prolonged and too severe.
Due to their colors and behavior, they are a real eye-catcher in any non-Mbuna Malawi aquarium. Even in a larger group in a suitably designed species tank, they are a highlight.

My conclusion:
A very beautiful and also special Malawi predator species. With their gold yellow, shiny coloration, the bluish head of the males, and their slim, torpedo-shaped body, they represent a true highlight in the aquarium.
They are very fast swimmers, so one has to be careful when opening the aquarium that they do not jump out.

As mentioned, one of my favorite species from Lake Malawi. I have been keeping them for many years. However, one must ensure that they obtain good, stable offspring; unfortunately, there are also many overbred fish of this species available on the market! With which one usually only encounters significant problems in the aquarium! This can lead to large losses and casualties that cannot be remedied. There are also completely silver-colored fish of the species, which I do not find as appealing. The species is rarely found in Lake Malawi, and wild catches hardly come from Africa anymore.