MY FIRST RIO NEGRO BIOTOPE

A Complete Guide for Children and Parents (8–10 Years Old) by FLUVAL.

Explore. Create. Discover.

1. WELCOME TO THE AMAZON

Let’s explore one of the most famous rivers in the Amazon rainforest. Its name is the Rio Negro. The Rio Negro is located in South America and is part of the Amazon ecosystem.

Its water is very special:
✅ Soft
✅ Slightly acidic
✅ Amber colored
✅ Rich in roots and fallen leaves
✅ Home to many fish and plants

The Rio Negro is full of life.

This variety of living things is called biodiversity.

Rio Negro Basin, Brazil. ©BAP, photo Natasha Khardina

2. WHAT IS BIOTOPE?

A biotope is a small copy of a natural habitat.
Our aquarium will recreate a tiny part of the Rio Negro.

BIN, Rio Preto, Rio Araca. ©BAP, photo N. Khardina

We will use:

💧 Water
🌳 Roots
🍂 Leaves and botanicals
🌿 Plants
🐟 Fish

Together they create a living ecosystem. An ecosystem is made of:

Biotope = the environment
Community = the living organisms
Together they form nature.

Igarapé do Aturiá, Rio Negro, Brasil. @BAP, photo by Andre Muxagata Minguini

3. WHAT DO WE NEED?

Aquarium Equipment

• Aquarium 17L
• Filter
• Heater
• Thermometer
• Aquarium Light
• Magnet Cleaner
• Fish Net

Natural Materials

• Fine sand
• Root or driftwood
• Plants
• Leaves and botanicals

Animals

• Cardinal Tetras (Paracherodon axelrodi)
• Snails

Optional:

• One Ancistrus sp.

Paracheirodon axelrodi, Cano Sardina, Rio Atabapo, Colombia. ©BAP, photo N. Khardina

Water Care and Maintenance Products

• Fluval Cycle Biological Enhancer
• Askoll Diet Microgranuli
• Water Test

4. CHOOSING THE RIGHT PLACE

Place the aquarium:

✅ On a strong and level surface
✅ Away from direct sunlight
✅ Away from radiators
✅ Away from air conditioners
✅ In a quiet area

Do not place the aquarium near a window.

Too much sunlight can cause algae growth and overheating.

BUILDING THE HABITAT

Step 1

Install the filter according to the instructions.

Step 2

Add the fine sand.
The sand represents the river bottom.

Step 3

Add the root or driftwood.
Roots are one of the most important features of the Rio Negro.

Step 4

Add leaves and botanicals around the roots.
These natural materials help create the appearance of a real Amazon habitat.

5. IDEAL WATER CONDITIONS

To create a healthy Rio Negro biotope, the water must be stable and natural.

The ideal conditions are:

🌡️ Temperature: 25–27°C
⚗️ pH: 6–7
💧 Water: soft and slightly acidic

These conditions help fish feel safe and show natural behaviour.

Always check the water regularly and keep conditions stable.

Small changes are better than big changes.

6. PREPARING THE WATER

Good news!

You can use normal tap water.

Step 1

Fill the aquarium with water.

Step 2

Cycle contains beneficial bacteria that help establish and maintain a healthy biological balance in the aquarium.

Dosage for a 20-Litre Aquarium

At Aquarium Setup

Add 2.5 mL of Cycle.

After Adding Fish, Replacing Filter Media, Medication Treatments, or Water Changes

Add 2.5 mL of Cycle.

Weekly Maintenance

Add 2.5 mL of Cycle.

Beneficial bacteria support the biological filter, help break down waste, and contribute to a healthy and stable aquatic ecosystem.

7. ADDING THE PLANTS

Plants are an important part of every ecosystem.

They:

🌿 Produce oxygen
🌿 Provide shelter
🌿 Absorb nutrients
🌿 Help keep the aquarium healthy

How to Plant

Remove the plant from its pot.
Carefully remove the rock wool.
Make a small hole in the sand.
Place the roots into the substrate.
Cover the roots gently with sand.

Only the roots should be buried.

Do not cover the leaves.

Try to create:

🌿 A planted area
🌳 A root area
🐟 An open swimming area

8. STARTING THE AQUARIUM

Switch on:

✅ Filter
✅ Heater
✅ Light

Check the temperature.

The ideal temperature is:

🐟 25–27°C

The ideal pH is:

💧 6–7

Allow the aquarium to run and stabilise before adding fish.

9. ADDING THE FISH

Fish need time to adapt to their new home.

Acclimation

Float the closed bag in the aquarium for 15 minutes.
Add a small cup of aquarium water to the bag.
Wait 10 minutes.
Repeat once more.
Wait another 10 minutes.
Gently release the fish.

Never pour the shop water into the aquarium.

10. WHO LIVES IN OUR BIOTOPE?

Cardinal Tetras

Cardinal Tetras (Paracherodon axelrodi) are colourful schooling fish.

They should always live in a group.

For a 30-litre aquarium:

Maximum 10 Cardinal Tetras

Snails

Snails help consume organic leftovers

Optional

One Ancistrus sp. may be added if suitable for the aquarium size and setup

Paracherodon axelrodi, Rio Negro, Brazil. ©BAP, photo M. Jordi

11. FEEDING THE FISH

Feed the fish once each day.

Daily Food

Askoll Diet Microgranuli

Give only a small amount.

The fish should finish all food within 2–3 minutes.

Too much food can pollute the water.

12. TESTING THE WATER

Healthy water helps fish and plants stay healthy.

Use Water Test every week.

Check the water regularly and keep a record of the results.

Good aquarists observe and learn from nature.

13. WATER CHANGES

In nature, rivers are always renewed.

In an aquarium, we must help maintain clean and stable water conditions.

Every Week

Change 20–25% of the water.

For a 20-litre aquarium:

Remove about 4–5 litres and replace it with fresh tap water treated with Aqua Plus.

Important Rules

❌ Never replace all the water
❌ Never use soap or detergents inside the aquarium
❌ Never add untreated tap water
❌ Avoid very cold or very hot water

Always prepare new water with Aqua Plus before adding it to the aquarium.

Water changes help remove waste, reduce nitrates and keep the ecosystem stable.

14. DAILY, WEEKLY AND MONTHLY CARE

Every Day

✅ Feed the fish
✅ Check the fish
✅ Check the temperature

Every Week

✅ Test the water using the Water Test
✅ Change 20–25% of the water
✅ Add Aqua Plus to new water
✅ Clean the glass using the Edge Algae Magnet

Every Month

✅ Add Plant Gro+
✅ Check equipment
✅ Check plant growth

Every 2–3 Months

✅ Add new leaves and botanicals
✅ Remove materials that have fully decomposed

Keep it simple, observe nature and enjoy your Amazon rainforest at home.

15. SAFETY RULES

Always wash your hands before and after working in the aquarium.

Never use cleaning products inside the aquarium.

Ask an adult for help when working with electrical equipment.

Always unplug electrical equipment before maintenance.

Keep the aquarium lid closed whenever possible.

16. WHAT MAKES A RIO NEGRO BIOTOPE?

A Rio Negro biotope includes:

💧 Water
🌳 Roots
🍂 Leaves and botanicals
🌿 Plants
🐟 Fish
👉 Good bacteria

Every part has an important role.

Together they create a living Rio Negro ecosystem.

Roots provide shelter.
Leaves and botanicals release natural substances into the water.
Plants help support life.
Fish are part of the community.
Good bacteria help keep the aquarium healthy.

This is how a Rio Negro biotope works.

Explore nature. Create a biotope. Discover biodiversity.

17. WHERE TO BUY YOUR FISH

For this biotope aquarium, we recommend:

7-8 Cardinal Tetra (Paracheirodon axelrodi)

We recommend purchasing your fish from trusted retailers that specialize in tropical freshwater species and follow proper animal welfare and quarantine procedures.

Recommended supplier:

Before purchasing, always ensure that the fish are healthy, active, and free from signs of disease or injury.

A healthy group of Cardinal Tetras will display vibrant colours, active schooling behaviour, and will quickly become the focal point of your biotope aquarium.