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Aquarium care guides
A good next step for your aquarium. Choose a collection, find your question and take it one guide at a time.
31 source-linked guides · 2–3 minutes each
Where would you like to start?
29 guidesFreshwaterFrom your first freshwater tank to everyday fishkeeping. Find setup, planted care and the shared foundations.Explore collection Photo: Ganeshk · CC BY-SA 3.0
29 guidesSaltwater & reefPlan a marine aquarium, explore reef basics and build steady care habits. Shared guides flag where system-specific advice matters.Explore collection Photo: Tappinen · CC BY-SA 3.0
4 guidesPlants & aquascapingBuild a planted freshwater aquarium around light, plants and a layout you can maintain.Explore collection Photo: Abhik.Mazumdar.73 · CC BY 4.0
15 guidesWater & maintenanceMake sense of water tests, prepare replacement water and keep a useful maintenance routine.Explore collection 
16 guidesEquipment & setupPlan the setup, understand the equipment and prepare for the things that can go wrong.Explore collection Photo: 16toki · Public domain
8 guidesFish health & behaviourGet to know your fish, plan new arrivals and recognize changes that need attention.Explore collection Photo: Anthony Corda · CC BY-SA 3.0
Browse all 31 guides
- Beginner aquarium setupChoose species, plan the tank, verify the cycle, then stock slowly.3 min read
- Starting a freshwater aquariumSource water, cycling and stocking order for a freshwater tank.3 min read
- Starting a saltwater aquariumSystem type, salt mixing and cycle checks for a marine tank.2 min read
Planning a build: what to buy firstAnimals, then the room, then the tank, then equipment.3 min read
Your tank's real water volumeThe number on the box is not the water inside. Measure it.3 min read
Cycling and water testingCheck the cycle with measured results before stocking.2 min read
Water parameters explainedWhat each reading measures and how they change each other.2 min read
Using a test kit correctlyExpiry, timing, honest colour reading and units.3 min read- Water changesWhat a change removes and how to do it safely.2 min read
Maintenance and observationA routine built around what the tank shows you.2 min read
Source water: tap, well, and purifiedChlorine, chloramine, well water and RO are different problems.2 min read
Aeration and dissolved oxygenHow aeration works and how to respond to distress.2 min read
Cloudy water: causes and fixesUse water tests and recent changes to investigate haze.2 min read
Algae causes and controlAlgae follows light and nutrients. Change the inputs.2 min read
Dosing safely from a labelA label gives a ratio. Scale it to your real volume.2 min read
Filtration explainedMechanical, biological, chemical: which media to protect.2 min read
Temperature and heatingMaintain a suitable temperature. Place heaters safely.2 min read
Lighting and photoperiodIntensity, spectrum and day length are separate choices.2 min read
Substrate and hardscapeHow materials affect chemistry, shelter and water flow.2 min read
What equipment specs actually meanWhich box numbers are measured and which are assumed.2 min read
Power outages and equipment failureSupport aeration while checking temperature and equipment.2 min read
Moving or upgrading an aquariumProtect the biofilter and check conditions after the move.2 min read
Stocking and compatibilityAdult size, water overlap, space and temperament.3 min read
Acclimating new arrivalsWhat happens in the bag and why bag water stays out.2 min read
Quarantine and biosecuritySeparate new arrivals to reduce disease transmission.2 min read
Early warning signs of illnessWhat to watch, what to check first, when to get help.2 min read- Reading normal behaviourKnow each fish's normal so a change means something.2 min read
Feeding and nutritionNeeds differ by species. Overfeeding shows up in the water.2 min read
Reading a fish food labelIngredients, guaranteed analysis, size and storage.2 min read- Planted tank basicsLight, substrate and CO2 working together. Start low-tech.2 min read
Reef tank basicsLive rock, measured salinity and what a skimmer removes.2 min read
Educational, not veterinary advice. Check species needs against current sources, follow the current label for any product, and see a qualified aquatic veterinarian for severe, urgent or uncertain health problems. How Fishician sources and reviews guides. Photographer credits and licenses appear beneath the relevant guide images.