Aquarium Lessons

Learn aquarium care, setup, and design — from beginner to advanced.

Aquascaping lesson library scene with planted aquarium, open books and study materials

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Choose a topic to find lessons that answer your questions.

Standard Beginner Aquarium on a Desk
Beginner Aquariums 10 lessons

Beginner Aquarium Guide: Complete First Tank Roadmap

Start your first aquarium with a clear beginner roadmap for tank size, setup, equipment, plants, cycling, fish, maintenance and mistakes.

Aquarium Water Guide Image
Water 22 lessons

Aquarium Water Guide: Parameters, Cycling & Stability for Healthy Freshwater Tanks

Understand aquarium water, cycling, ammonia, nitrite, nitrate, pH, KH, GH, oxygen and water changes — the foundation of every stable freshwater tank.

Lush planted aquarium with foreground, midground and background plants, visible layered substrate and driftwood in cross-section view
Plants 32 lessons

Aquarium Plants: Complete Guide to Plant Types, Layering & Nutrient Balance

Learn how to choose, layer, and grow aquarium plants successfully. Complete guide to carpeting, midground, background and epiphyte plants plus NPK and micronutrient balance for stable planted tanks.

Ultra realistic freshwater aquarium setup with LED lighting, external canister filter and professional CO₂ system – complete aquarium equipment guide
Equipment 18 lessons

Aquarium Equipment Guide: Complete Setup for Lighting, Filtration, CO₂ & Structural Safety

Plan a freshwater aquarium setup with the essential equipment: filter, heater, lighting, CO2, stand, glass, substrate, tools, and safety checks.

Ultra-realistic aquarium hardscape with natural rocks, driftwood and visible sand and soil substrate layers in cross-section view
Hardscape 5 lessons

Aquarium Hardscape Guide: Rocks, Driftwood, Sand & Substrate Foundations

Master aquarium hardscape with rocks, driftwood, soil, sand and lava layers. Build stable layouts, avoid mistakes, and design cleaner aquascapes.

Aquarium Fish Shrimp Snails
Livestock 8 lessons

Aquarium Fish, Shrimp & Snails Guide: Building a Balanced Ecosystem

Learn how fish, shrimp, and snails work together to create a stable aquarium ecosystem. Build a balanced tank step by step.

Aquarium Styles Guide hero image showing Nature, Iwagumi, Dutch, Diorama and Biotope aquascaping styles
Style 5 lessons

Aquarium Styles Guide: Nature, Iwagumi, Dutch, Diorama & Biotope

Looking for aquascaping inspiration? Explore the most popular aquarium styles, layout concepts and design techniques used in modern planted tanks.

Aquarium maintenance tools in use including gravel vacuum, aquascaping tweezers and water change hose in a planted tank with layered substrate
Tools 3 lessons

Aquarium Tools: Cleaning, Maintenance & Water Change Systems

Find the best aquarium tools for cleaning, trimming, and water changes. Create a simple maintenance routine that keeps your tank clear and stable.

A left wood group with small attached plants leaves open sand and water on the right.
Aquascaping 7 lessons

Aquascaping Guide: Design, Layout, Styles & Techniques

Learn how to plan an aquascape, choose a layout, combine hardscape and plants, and maintain the design. A practical aquascaping guide for beginners.

Start here roadmap

A practical path through the early decisions that shape a healthy aquarium.

  1. 1 Choose your setup First Aquarium Checklist: Complete Beginner Setup Guide Beginner 14 min.
  2. 2 Understand cycling How Long Does Aquarium Cycling Take? Timeline, Tests & Ready Signs Beginner 12 min.
  3. 3 Pick beginner fish Beginner Community Fish: Peaceful Tank Guide Beginner 18 min.
  4. 4 Learn water changes Aquarium Water Change Schedule: How Often & How Much Water to Change Beginner 12 min.
  5. 5 Avoid common mistakes Beginner Aquarium Guide: Complete First Tank Roadmap Beginner 20 min.

What’s going wrong in your aquarium?

Find solutions to the most common aquarium problems.

Fish gasping at the surface Fish Gasping at the Surface White spots on fish Ich / White Spot Disease in Aquarium Fish Fish not eating Fish Not Eating: Causes, Safe Checks & When to Act Fish hiding or clamping fins Fish Stress Signs: Hiding, Clamped Fins, Colour Loss & More Cloudy water Cloudy Aquarium Water Ammonia spike Ammonia Spike in Aquarium Nitrite spike Nitrite Spike in Aquarium High nitrate High Nitrate in Aquarium Identify algae problems Aquarium Algae Library Aquarium plants melting Aquarium Plant Deficiency Guide CO2 problems CO2 Troubleshooting Guide pH too high Aquarium pH Too High pH too low Aquarium pH Too Low Filter flow or performance issues Aquarium Filter Flow Guide

New & updated lessons

Freshwater aquarium fish being fed flakes, with food sinking toward the bottom.
Food
Beginner 5 min.

How to Feed Aquarium Fish: How Much and How Often?

FeaturedImage_Fishfood
Food
Beginner 15 min.

Best Aquarium Fish Food: 7 Picks by Fish Type & Feeding Zone

Cloudy aquarium water in a freshwater tank with plants and hardscape
Water
Beginner 12 min.

Cloudy Aquarium Water: Causes, Types & Safe Fixes

Aquarium with White vs RGB Aquarium Lighting Difference
Equipment
Beginner 12 min.

White vs RGB Aquarium Lighting: Which Is Better for Planted Tanks?

KH versus GH comparison with aquarium water testing tools
Water
Beginner 12 min.

KH vs GH: Carbonate Hardness vs General Hardness in Aquariums

Aquarium filter beside a clear planted freshwater tank
Equipment
Beginner 12 min.

Canister vs Sponge Filter

Browse all lessons

Keep exploring with practical guides, comparisons, setup help, and troubleshooting lessons.

Freshwater aquarium fish being fed flakes, with food sinking toward the bottom.
Food
Beginner 5 min.

How to Feed Aquarium Fish: How Much and How Often?

FeaturedImage_Fishfood
Food
Beginner 15 min.

Best Aquarium Fish Food: 7 Picks by Fish Type & Feeding Zone

Cloudy aquarium water in a freshwater tank with plants and hardscape
Water
Beginner 12 min.

Cloudy Aquarium Water: Causes, Types & Safe Fixes

Aquarium with White vs RGB Aquarium Lighting Difference
Equipment
Beginner 12 min.

White vs RGB Aquarium Lighting: Which Is Better for Planted Tanks?

KH versus GH comparison with aquarium water testing tools
Water
Beginner 12 min.

KH vs GH: Carbonate Hardness vs General Hardness in Aquariums

Aquarium filter beside a clear planted freshwater tank
Equipment
Beginner 12 min.

Canister vs Sponge Filter

First Beginner Aquarium with Items as a Checklist
Beginner Aquariums
Beginner 14 min.

First Aquarium Checklist: Complete Beginner Setup Guide

Stable aquarium pH test beside a healthy planted freshwater tank
Water
Intermediate 12 min.

Stable Aquarium pH: How to Prevent Swings, Crashes & Fish Stress

Aquarium filter beside a clear planted freshwater tank
Equipment
Beginner 14 min.

Best Aquarium Filter: How to Choose the Right Filter for Your Tank

Aquarium Plant deficiencys
Plants
Beginner 20 min.

Aquarium Plant Deficiency Guide: Symptoms, Causes & Fixes

Peaceful beginner community fish swimming in a planted freshwater aquarium
Beginner Aquariums
Beginner 18 min.

Beginner Community Fish: Peaceful Tank Guide

Aquarium with Par Meter explaining how much light you actually need
Equipment
Beginner 19 min.

How Much Light Do Aquarium Plants Need?

Different Aquarium LED for best LED Light for Planted Aquarium
Equipment
Beginner 14 min.

Best LED Light for Planted Aquarium

Aquarium Aquascape Lighting
Equipment
Intermediate 11 min.

Aquarium Lighting Guide: How to Choose the Right Light

Water circulation and filter flow in a planted freshwater aquarium
Equipment
Intermediate 14 min.

Aquarium Filter Flow Guide: Circulation, Dead Spots & Ideal Flow Rate

Aquarium pH test showing low pH beside a planted freshwater tank
Water
Intermediate 12 min.

Aquarium pH Too Low: Causes, Risks & Safe Ways to Raise pH

Freshwater aquarium with high pH reading, test kit, mineral rocks and driftwood for safely lowering aquarium pH
Water
Intermediate 12 min.

Aquarium pH Too High: Causes, Risks & Safe Ways to Lower pH

Freshwater planted aquarium with pH test kit, digital pH meter and healthy fish showing stable aquarium pH monitoring
Water
Beginner 13 min.

Aquarium pH Guide: How to Keep pH Stable in Freshwater Tanks

KH and GH aquarium test kits beside a planted freshwater tank
Water
Beginner 13 min.

Aquarium KH and GH Guide: Hardness, Minerals & pH Stability

6500K Aquarium Lighting Explained What It Means for Plants, Fish, and Aquascaping
Equipment
Beginner 14 min.

6500K Aquarium Lighting Explained: What It Means for Plants, Fish, and Aquascaping

feauturedimage_co2
Equipment
Beginner 17 min.

Aquarium CO2 System Guide: How to Boost Plant Growth Like a Pro

Low-tech planted aquarium with dense green carpet plants growing without visible CO2 equipment
Plants
Beginner 18 min.

Carpet Plants Without CO₂: Best Low-Tech Aquarium Carpets

iwagumi_featuredimage
Style
Intermediate 17 min.

Iwagumi Aquascape Guide: How to Design a Stunning Minimalist Aquarium Layout

Diorama Aquascaping
Style
Intermediate 22 min.

Diorama Aquascaping: Perspective Layouts, Depth & Plant Scaling

FeaturedImage_LavaGranules
Hardscape
Intermediate 19 min.

Aquarium Lava Granules Guide: How to Use Lava Rock as a Foundation Layer in Aquascaping

Aquarium Sand Aquascape
Hardscape
Beginner 8 min.

Aquarium Sand: Complete Guide to Safe Use, Aesthetics & Maintenance

Aquarium KH test kit beside a planted freshwater tank
Water
Beginner 11 min.

KH Explained: Carbonate Hardness, pH Stability & Safe Adjustment

Aquarium with Monte Carlo Aquarium Plant
Plants
Beginner 18 min.

Monte Carlo Aquarium Plant Guide: Carpet Care & Planting

Planting Aquarium Root Tabs
Plants
Beginner 18 min.

Aquarium Root Tabs Guide: Substrate Fertilizer for Plants

Healthy planted aquarium with fish and oxygen-rich water movement
Water
Intermediate 12 min.

Aquarium Oxygen Levels: Low Oxygen Signs, Causes & Safe Fixes

featuredimage_macronutrients
Plants
Intermediate 15 min.

Macronutrients for Aquarium Plants: Complete Guide to NPK, Dosing & Healthy Growth

Dutch Style Aquarium Aquascape
Style
Intermediate 20 min.

Dutch Style Aquarium: Plant Streets, Contrast & Layout Rules

Aquarium Stand
Equipment
Beginner 13 min.

How to Choose an Aquarium Stand: Size, Weight, Height and Floor Safety

biotope_featuredimage
Style
Intermediate 17 min.

Biotope Aquarium Guide: Build the Most Natural Tank Ecosystem

A higher left wood-and-stone group and lower right shelf frame a visible route into smaller rear layers.
Aquascaping
Intermediate 12 min

Aquascaping Contests: Competitions, Judging & Preparation

A camera on a tripod faces a planted Nature Aquarium in a dim room under its overhead light.
Aquascaping
Intermediate 12 min

Aquascape Photography: Camera Settings, Lighting & the Perfect Contest Shot

Dense unequal green plant groups frame a central opening above low weathered stones in a mature-looking aquarium.
Aquascaping
Intermediate 9 min

Contest Aquascaping: From Layout to the Final Photo

One large irregular right-hand rock and lower companions form a clear main group.
Aquascaping
Beginner 14 min

Aquascaping Design Principles: Layout, Balance & Focal Points

Near wood on the left overlaps a smaller rear group beyond an open sand route.
Aquascaping
Intermediate 14 min

Aquascaping Depth: Perspective, Scale & Substrate Slopes

A compact wood-and-plant island leaves open sand around it in a cube aquarium.
Aquascaping
Beginner 12 min

Nano Aquascaping: Design a Small Tank with Depth & Balance

Two stacked views of the same wood-led layout compare scattered loose foreground stones above with an open sand foreground below.
Aquascaping
Beginner 12 min

Aquascaping Mistakes: Why a Layout Looks Wrong & How to Fix It

Takashi Amano Nature Inspired Aquascape Aquarium
Style
Intermediate 25 min.

Nature Aquarium: Complete Nature Aquascaping Style Guide

feauturedimage_carpeting_plants
Plants
Intermediate 15 min.

Aquarium Carpeting Plants: Complete Guide to the Best Foreground Plants, Planting and Care

FeaturedImage_AquariumPlantcare_Tools
Tools
Beginner 8 min.

Aquarium Plant Tools Guide for Care and Maintenance

FeaturedImage_CleaningTools
Tools
Beginner 7 min.

Aquarium Cleaning Tools: The Ultimate Guide for a Spotless Tank

Livestock
Beginner 12 min.

Ich / White Spot Disease in Aquarium Fish: Signs, Causes & Safe Next Steps

Aquarium water change mistakes showing dirty cloudy water during siphoning and a clean planted freshwater tank
Water
Beginner 12 min.

Aquarium Water Change Mistakes: Common Problems & Safe Fixes

Aquarist performing an emergency water change in a cloudy freshwater aquarium with a siphon and bucket
Water
Beginner 12 min.

Emergency Aquarium Water Change: When, How Much & Safe Steps

Aquarium during cycling process
Water
Beginner 12 min.

How Long Does Aquarium Cycling Take? Timeline, Tests & Ready Signs

Aquarium GH water test kit beside a planted freshwater tank
Water
Beginner 11 min.

GH Explained: General Hardness, Minerals & Aquarium Health

Nature Scenery with Aquarium Lighting for deep Tanks
Equipment
Beginner 17 min.

Aquarium Lighting for Deep Tanks: How to Grow Plants in Tall Aquariums

featuredimage_aquariumsoil
Hardscape
Beginner 8 min.

Aquarium Soil Guide: Choosing, Installing & Maintaining Nutrient-Rich Substrate

featuredimage_aquariumdriftwood
Hardscape
Beginner 8 min.

Aquarium Driftwood Guide: Types, Preparation, DIY Collection & Aquascaping Tips

Aquarium Midground Plants
Plants
Beginner 13 min.

Aquarium Midground Plants: Full Guide to Placement, Best Species & Styling Tips

Planted aquarium with green algae caused by excessive lighting
Equipment
Beginner 20 min.

Aquarium Lighting and Algae: Why Light Causes Algae and How to Prevent It

Illustration Aquarium with a transparent Par Aquarium Lighting Chart
Equipment
Beginner 7 min.

Aquarium PAR Explained: How to Read PAR Charts

Low Tech Aquarium with a cheap Aquarium Light and low light plants
Equipment
Beginner 17 min.

Low Tech Aquarium Lighting Guide: Simple Light for Stable Planted Tanks

FeaturedImage_AquariumGlass
Equipment
Intermediate 19 min.

Aquarium Glass Types: Float, Low-Iron, Tempered & Rimless

Aquarium Background Plants Vallisneria, Bacopa, Rotala
Plants
Beginner 22 min.

Best Aquarium Background Plants: Tall Species by Size, Light and CO₂

Aquarium Fertilizer for Guide Hero Image
Plants
Beginner 20 min.

Aquarium Fertilizer Guide: Complete Plant Nutrient Basics

Beginner Planted Tank with no co2
Beginner Aquariums
Beginner 17 min.

No CO₂ Planted Tank: Beginner Low-Tech Guide

Cloudy new freshwater aquarium with fish, plants and water test kits showing new tank syndrome symptoms
Water
Beginner 11 min.

New Tank Syndrome Guide: Symptoms, Causes & Safe Fixes for New Aquariums

Aquarium and Aquascaping Epiphyte Plants Anubias, Bucephalandra, Fern
Plants
Beginner 14 min.

Epiphyte Aquarium Plants: How to Mount, Care & Grow Them Properly

Aquarium water parameter test kits beside a planted freshwater tank
Water
Intermediate 13 min.

Aquarium Water Parameters Guide: Testing, Meaning & Stability

featuredimage_cleaningtools
Tools
Beginner 11 min.

Aquarium Water Change Tools Guide: Siphons, Pumps & DIY Systems

Aquarium and Aquascaping Stone Rock Types
Hardscape
Beginner 13 min.

Types of Aquarium Rocks: Safe Stones, Water Chemistry & Aquascaping

Anubias aquarium plant growing on hardscape in a planted freshwater tank
Plants
Beginner 17 min.

Anubias Aquarium Plant Guide: Care, Planting & Placement

Livestock
Beginner 12 min.

Fish Stress Signs: What to Check Before Assuming Disease

Livestock
Beginner 10 min.

Acclimating New Fish: A Safer Arrival Routine

Livestock
Beginner 12 min.

Quarantine Aquarium Fish: Setup, Observation & Safe Transfer

Livestock
Beginner 11 min.

Fish Not Eating: Causes, Safe Checks & When to Act

Fishless cycling setup with test tubes beside a planted aquarium
Water
Beginner 13 min.

Fishless Cycle Guide: How to Cycle an Aquarium Without Fish

Freshwater aquarium water change schedule with calendar, siphon, bucket and clean planted tank
Water
Beginner 12 min.

Aquarium Water Change Schedule: How Often & How Much Water to Change

Cloudy freshwater aquarium with fish and test kits showing high nitrate levels in an aquarium
Water
Beginner 12 min.

High Nitrate in Aquarium: Causes, Risks & Safe Ways to Lower Nitrate

Planted freshwater aquarium with fish and water test kits illustrating a nitrite spike in an aquarium
Water
Intermediate 12 min.

Nitrite Spike in Aquarium: Causes, Fish Symptoms & Safe Emergency Fixes

Aquarium ammonia spike guide with fish, water testing kit and planted freshwater tank
Water
Intermediate 12 min.

Ammonia Spike in Aquarium: Causes, Fish Symptoms & Emergency Fixes

Fish on surface because of too much CO2
Plants
Beginner 18 min.

Signs of Too Much CO₂ in Aquariums: Safety Guide

Aquarium with easy plants for beginners
Beginner Aquariums
Beginner 16 min.

Easy Aquarium Plants for Beginners: Best Starter Guide

Canister filter with biological, mechanical and chemical aquarium filter media beside a planted freshwater tank
Equipment
Intermediate 11 min.

Aquarium Filter Media Guide: Biological, Mechanical & Chemical Filtration

featuredimage_micronutrients
Plants
Intermediate 17 min.

Aquarium Micronutrients Guide: Boost Plant Health the Right Way

aquarium_floating_plants_900x600
Plants
Intermediate 12 min.

Floating Aquarium Plants: Best Species for Your Planted Tank

Aquarium starter bacteria bottle for cycling a new freshwater tank
Water
Intermediate 19 min.

Aquarium Starter Bacteria: Complete Guide to Cycling & Water Health

Aquarium CO2 diffuser releasing fine bubbles in a planted aquascape with rocks and carpeting plants
Plants
Beginner 18 min.

Aquarium CO₂ Diffuser Guide: Placement, Types & Flow

Nano aquarium with compact midground plants, rocks, driftwood, and green foreground growth
Plants
Beginner 18 min.

Nano Midground Aquarium Plants: Best Small Plants for Tiny Tanks

Liquid carbon bottle placed beside a planted aquarium with green aquatic plants
Plants
Beginner 18 min.

Liquid Carbon Aquarium Guide: Is It a CO₂ Alternative?

featuredimage_aquaticmoss
Plants
Beginner 17 min.

Aquarium Moss Guide: Types, Care and How to Attach It

Beginner fish for Aquarium
Beginner Aquariums
Beginner 13 min.

Easy Fish for Beginners: Best First Aquarium Fish

Betta Fish in an Aquarium Bowl
Beginner Aquariums
Beginner 14 min.

Betta Bowl Aquarium

Java Fern on Wood
Plants
Beginner 17 min.

Java Fern Aquarium Plant Guide: Care, Planting & Propagation

Aquarium Plants with calcium deficiency
Plants
Beginner 18 min.

Calcium Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium with CO2 Diffusor
Plants
Beginner 19 min.

CO₂ Troubleshooting Guide: Fix Planted Tank CO₂ Problems

EI Method Dosed Aquarium
Plants
Beginner 19 min.

EI Dosing Guide: Estimative Index for Planted Aquariums

Aquarium with Lean Dosing
Plants
Beginner 19 min.

Lean Dosing Guide: Controlled Fertilizing for Planted Tanks

CO2 reactor installed on a planted aquarium with dense aquatic plants and visible tubing
Plants
Beginner 18 min.

CO₂ Reactor Guide: Efficient CO₂ for Planted Aquariums

Aquarium CO2 bubble counter releasing bubbles in front of aquatic plants
Plants
Beginner 18 min.

CO₂ Bubble Rate Guide: Bubbles Per Second for Planted Tanks

Glass CO2 drop checker with green indicator liquid inside a planted aquarium
Plants
Beginner 18 min.

CO₂ Drop Checker Guide: Read Aquarium CO₂ Correctly

Close-up of Bucephalandra aquarium plant attached to driftwood in a planted tank
Plants
Beginner 17 min.

Bucephalandra Aquarium Plant Guide: Care, Planting & Placement

Aquarium cycling setup with water test kit beside a new planted freshwater tank
Water
Beginner 24 min.

Aquarium Cycling Guide: How to Cycle a New Aquarium Safely

featuredimage_aquariumshrimp
Livestock
Intermediate 11 min.

Aquarium Shrimp Guide: Build a Stable Shrimp Tank

featuredimage_aquariumsnales
Livestock
Intermediate 10 min.

Aquarium Snails Guide: Build a Balanced Tank

Featuredimage_Aquariumfish
Livestock
Intermediate 10 min.

Aquarium Fish Guide: Build the Perfect Tank Setup

featuredimage_aquariumfilter
Equipment
Beginner 22 min.

Aquarium Filter Guide: Types, Media, Setup and Maintenance

Aquarium Plants with iron deficiency
Plants
Beginner 18 min.

Iron Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium Plants with potassium deficiency
Plants
Beginner 18 min.

Potassium Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium Plants with phosphate deficiency
Plants
Beginner 18 min.

Phosphate Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium Plants with Nitrogen deficiency
Plants
Beginner 18 min.

Nitrogen Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium Plants with magnesium deficiency
Plants
Beginner 18 min.

Magnesium Deficiency in Aquarium Plants: Symptoms & Fixes

Aquarium with Nano fish for beginner
Beginner Aquariums
Beginner 20 min.

Best Nano Fish: Small Fish for Beginner Aquariums

Low Maintenance Aquarium
Beginner Aquariums
Beginner 16 min.

Low Maintenance Aquarium: Easy Beginner Setup Guide

Beginner Aquarium size
Beginner Aquariums
Beginner 15 min.

Best Beginner Aquarium Size: First Tank Guide

Dirty Aquarium with Beginner Mistakes
Beginner Aquariums
Beginner 16 min.

Beginner Aquarium Mistakes: Avoid First Tank Problems

Aquarium Lighting Schedule Guide How to Set the Perfect Photoperiod of 8 Hours
Equipment
Beginner 16 min.

Aquarium Lighting Schedule Guide: How to Set the Perfect Photoperiod

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