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Construction of the Boulogne Aquarium

Overview of the Project

• The aquarium in Boulogne-sur-Mer is nearing completion, with significant structural elements like the framework and roof already in place. Artisans are working on installing a large glass facade that will enhance its appearance.

Water Supply System

• To fill the massive tank, 10 million liters of seawater are required, sourced from 300 meters offshore in the English Channel. Engineers have developed a sophisticated pumping system hidden beneath Boulogne beach to facilitate this process.

Underground Infrastructure

• Four pipes, each 250 meters long and buried five meters deep, draw seawater directly to the aquarium's center. A total of 17 kilometers of underground piping has been installed to supply Europe’s largest tank with water.

Water Management Technology

• Frédéric Cousin oversees water management at Nozika; raw seawater enters through a newly installed pipe controlled by an advanced system that adjusts based on tidal coefficients. This technology ensures optimal water flow into the aquarium.

Control Systems

• The control unit appears ordinary but functions as the brain of the aquarium, dynamically regulating water intake according to tide changes—maximizing seawater capture during high tides for efficient filling.

Filling Process Initiation

• The filling process for the main tank is set to begin shortly; currently, a large glass panel is secured with silicone joints and metal framing in preparation for pressure once filled with water.

Structural Integrity Measures

• Once filled, the weight of 500 tons of water will press against this glass panel; engineers designed a ceiling slab over one meter thick to withstand immense pressure exerted by the water on this structure. This design accounts for significant upward force from the tank's contents.

Final Preparations Before Filling

• Joël Taquet conducts final checks before filling begins; any metallic objects left behind could disrupt biological balance within the tank, posing risks to marine life housed there. Attention to detail is critical at this stage as errors could be irreversible post-filling.

Countdown to Filling Day

• Scheduled for dawn, filling marks a pivotal moment in construction—engineers François Gosselin and Frédéric Cousin initiate this long-awaited phase where approximately 30 cm of seawater will be added daily until full capacity is reached over six weeks. Only one chance exists for this operation due to cost considerations and existing infrastructure limitations used during filling operations.

Transitioning from Construction to Operation

• As daily increments accumulate towards full capacity (10 million liters), excitement builds among teams who see their hard work transform into an operational aquarium rather than just a construction site—a symbolic milestone marking new beginnings for aquatic life within its walls.

Quality Assurance Measures

• With only six months until opening day, teams rush to install lighting systems while ensuring rigorous testing protocols are followed regarding water quality and oxygen levels—critical factors influencing marine animal health within Europe's largest aquarium setup requiring state-of-the-art filtration systems designed specifically for such vast volumes of water management needs.

Innovative Filtration System

• Engineers have created an unprecedented filtration prototype located in the aquarium's basement; it consists of twelve massive filters weighing fifty tons each capable of purifying all aquarium water every four hours by removing waste materials effectively ensuring optimal living conditions for aquatic inhabitants.

Technological Marvel in Marine Filtration

Overview of the Installation

• This installation is one of the largest in the world and the biggest in Europe, featuring a total of 200 tons of sand for water filtration.

• The filter consists of four different layers of sand, each with specific granularity to capture various suspended particles effectively.

Water Quality Management

• Engineers have designed a 200 cubic meter water reserve to ensure autonomy for several weeks during ecological disasters like oil spills.

• Frédéric Cousin, responsible for water quality, conducts initial sampling to monitor physical and chemical parameters crucial for marine life survival.

Monitoring Parameters

• Regular checks include physical parameters (temperature, oxygen) and chemical parameters (ammonia, nitrates, nitrites, phosphates). All checked parameters are currently excellent.

• Confidence in operational success is high due to positive results from both physical and chemical assessments.

Coral Installation Process

Initial Coral Setup

• Aquarists at Nozika aim to produce 10,000 corals within a year; this ambitious goal has been successfully initiated with the first coral installations.

• Installing corals marks a significant step towards introducing larger marine animals into the aquarium environment. Preparation involves ensuring that tank walls are ready for coral attachment.

Coral Attachment Techniques

• Divers use phthalate-free plastic rods inserted into tank walls as supports for concrete domes where corals will grow. This method ensures safety for marine life during growth phases.

Acclimatization and Transfer Challenges

Introduction of Fish Species

• Following successful coral acclimatization, larger fish species are set to be introduced into the main basin shortly before the official opening date. The arrival is highly anticipated by marine specialists present at the site.

Handling New Arrivals

• The transfer process from transport tanks to their new habitat must be swift due to limited oxygen supply; stress management is critical during this delicate operation as fish adapt post-travel fatigue.

Post-transfer Care

• To help newly arrived fish regain energy after their journey, teams provide them with specially prepared fish puree via feeding bottles while they undergo quarantine before entering their permanent environment in the grand basin.

Introduction of Fish Species in Aquariums

Importance of Introduction Order

• The order of introducing fish species into the aquarium is crucial to prevent predation among them.

Feeding Dynamics

• When prey animals are introduced first, they establish territory, making it difficult for predators to dominate immediately. This helps maintain balance in the ecosystem.

• Proper feeding practices involve timing, frequency, and quantity to ensure all species thrive together.

Feeding Techniques

• To feed 60,000 marine animals at the center, over 40 tons of food is required annually, with specific diets tailored for each species.

• Target feeding involves training fish to respond to a visual cue (a cross sign) that indicates where food will be provided. This method ensures that each species receives its appropriate portion at scheduled times.

Water Clarity and Visibility Challenges

Managing Turbidity

• Maintaining optimal water clarity is essential for visitor experience while ensuring that marine animals do not see each other across the aquarium's expanse. A visibility limit of 17 meters has been set to enhance immersion effects for visitors.

Engineering Constraints

• Engineers face challenges in achieving this visibility without compromising the structural integrity and aesthetic appeal of the aquarium design; clear water can disrupt the intended immersive experience.

Adjusting Water Filtration

• Technicians will slow down filtration processes to slightly cloud the water, achieving desired turbidity levels while monitoring visibility using a reference disk placed underwater at 17 meters distance from viewing panels.

Transporting Endangered Shark Species

Arrival of New Marine Life

• A semi-truck arrives with three baby marten sharks sourced from Australia under special governmental permission due to their endangered status; such operations occur only once every five years globally.

Transport Conditions

• The sharks are transported in a specially designed container that maintains high oxygen levels (over 150%) and regulates temperature closely matching their natural habitat conditions during transit. This careful management minimizes stress on the animals during transport.

Acclimatization Process

• Upon arrival, technicians gradually replace water in the transport container with that from the main tank using a large hose, allowing sharks to acclimate smoothly to their new environment without shock or distress during transfer procedures.

Handling Precautions

• Careful handling techniques are employed as sharks lack skeletal protection around their thoracic cavity; specialized nets made from rubber mesh help distribute pressure evenly when moving these delicate creatures into their new home safely.

The Journey of Hammerhead Sharks in Quarantine

Quarantine Process for Hammerhead Sharks

• The hammerhead sharks are placed in a quarantine basin where they will undergo enhanced monitoring for several days to ensure their health and adaptation.

• If the acclimatization process goes as planned, these sharks will eventually move to the largest aquarium in Europe.

• There is an aspiration to breed these sharks, potentially leading to the first baby hammerheads in the future.

Maturity and Visitor Experience

• It will take approximately six years for the hammerhead sharks to reach sexual maturity, indicating a long-term commitment to their care and breeding.

• In just a few weeks, visitors will have the opportunity to admire these newly introduced sharks at the aquarium.

Completion of Construction

• The construction project has been completed successfully, with all animals now settled into their new environments.

• The teams involved achieved an impressive feat by transforming France's largest aquarium into Europe's largest aquarium ahead of schedule by one and a half months.

• Thanks to diligent efforts, Nozika now boasts 85 aquariums that collectively hold over 17 million liters of water.