Fix the water. Enjoy the fish.

Aquarium problems explained step by step, and the equipment designed for them. Research-based, beginner-friendly, no hype.

Browse Equipment
Explore Fishkeeping
Substrate, Plants & DecorGravel, sand and plant soil, live and artificial plants, rocks, driftwood and decor that are safe in a tank.49 guidesFilters & MediaCanister, hang-on-back, sponge and internal filters by tank size, plus the media inside them.69 guidesTanks & StandsTanks and starter kits by size and fish, and stands rated to carry them.32 guidesAir, CO2 & PumpsAir pumps and stones, water and return pumps, and CO2 systems for planted tanks.42 guidesLightingLED fixtures by tank length and use: fish-only, low-tech planted, high-light planted.19 guidesSaltwater & ReefReef and marine gear: all-in-one tanks, skimmers, powerheads, salt and auto top-off.24 guidesWater Care & TestingTest kits, conditioners, bacteria starters and treatments, each tied to the water problem it addresses.20 guidesCleaning & MaintenanceVacuums, siphons, scrapers, algae tools and buckets.16 guidesFood & FeedingFish food by species and diet, and automatic feeders for holidays.6 guidesHeaters & ThermometersHeaters by tank size and control type, and thermometers to check them.18 guides

Recent guides

Useful reading from Fishkeeping

New in Water Lab