15 foundational guides

Learn the system, not a collection of shortcuts.

Plain-English foundations for decisions that affect water quality, behaviour and long-term animal care.

01

Aquarium foundations

How to cycle a freshwater aquarium

Build a bacterial filter before livestock arrive, verify it with testing and add animals gradually.

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02

Aquarium foundations

The aquarium nitrogen cycle explained

Waste becomes ammonia, then nitrite, then less-toxic nitrate through microbial processes.

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03

Aquarium foundations

How to choose fish for a new tank

Start with adult size, water overlap and behaviour rather than colour or shop size.

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04

Aquarium foundations

How to introduce new fish safely

Quarantine, equalise temperature and minimise transport-water transfer where appropriate.

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05

Aquarium foundations

How many fish can go in a tank?

There is no single safe number; adult biomass, oxygen, territory and maintenance all interact.

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06

Aquarium foundations

Why one inch per gallon is unreliable

Length ignores body mass, shape, activity, waste, social needs and aquarium footprint.

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07

Aquarium foundations

How to measure aquarium volume

Internal water dimensions give a better estimate than the advertised tank size.

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08

Aquarium foundations

Understanding pH, GH and KH

These measures describe acidity, dissolved minerals and buffering; stability matters alongside the number.

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09

Aquarium foundations

How to acclimate aquarium fish

Temperature, water chemistry and transport duration decide the safest acclimation method.

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10

Aquarium foundations

How often to change aquarium water

Use testing, stocking and feeding to set a schedule, then keep it consistent.

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11

Aquarium foundations

How to choose an aquarium filter

Match flow, media capacity, oxygenation and maintenance access to the animals and tank.

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12

Aquarium foundations

How to choose an aquarium heater

Room-to-water temperature difference is more useful than a watts-per-litre slogan.

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13

Aquarium foundations

Beginner aquarium mistakes to avoid

Most early problems trace to rushing the cycle, incompatible livestock or unstable maintenance.

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14

Aquarium foundations

Schooling fish and minimum group sizes

A group is a behavioural need, not decoration, and many species become calmer in numbers above the minimum.

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15

Aquarium foundations

Understanding territorial aquarium fish

Territory depends on sight lines, floor plan, maturity, sex and breeding condition.

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