Fix the water. Enjoy the fish.
Aquarium problems explained step by step, and the equipment designed for them. Research-based, beginner-friendly, no hype.
Substrate, Plants & DecorGravel, sand and plant soil, live and artificial plants, rocks, driftwood and decor that are safe in a tank.46 guidesFilters & MediaCanister, hang-on-back, sponge and internal filters by tank size, plus the media inside them.61 guidesTanks & StandsTanks and starter kits by size and fish, and stands rated to carry them.28 guidesAir, CO2 & PumpsAir pumps and stones, water and return pumps, and CO2 systems for planted tanks.41 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.15 guidesWater Care & TestingTest kits, conditioners, bacteria starters and treatments, each tied to the water problem it addresses.24 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.15 guides
Recent guides
Cleaning & MaintenanceBest Algae Scrapers for Glass and Acrylic Aquariums: Magnetic and Handheld
Water Care & TestingBest Phosphate Removers for Aquariums: Media and Liquids for Freshwater and Reef
Water Care & TestingBest RO/DI Systems for Aquariums, Reef and Freshwater
Air, CO2 & PumpsBest Aquarium Air Pumps: 8 Picks Compared on Output, Noise and Tank Size
Heaters & ThermometersBest Aquarium Heaters of 2026: Picks by Tank Size and How to Choose One
Filters & MediaBest Fish Tank Filters in 2026: Hang-On-Back, Canister and Sponge Picks by Tank Size
Useful reading from Fishkeeping
Tank Setup & CareHow Often to Fertilize Aquarium Plants: Liquids and Root Tabs
Tank Setup & CareHow to Feed Your Fish While You’re on Vacation
Tank Setup & CareWhat to Do With a Fish Tank During a Power Outage