Blog
Short answers to the searches keepers actually make. Longer how-tos live in Guides. Numbers live in Tools.
- Why is my aquarium water cloudy?8 min read
Cloudy aquarium water is usually a bacterial bloom, overfeeding, or stirred substrate — not a mystery. Test ammonia. Do not dump clear-water potions first.
- How often to change aquarium water9 min read
Most stocked community tanks want a weekly 25% water change. Goldfish want more. Test nitrate and dose conditioner for the new water, not the whole tank.
- How many fish can fit in a 20-gallon tank?10 min read
A 20 gallon long can hold a tetra school and corydoras. A 20 high is worse for swimming. Inch-per-gallon is not the answer — adult size, waste, and filter GPH are.
- Fish that don't need heaters9 min read
Unheated aquarium fish: white cloud mountain minnows, zebra danios, goldfish. Room temperature matters. Tropical tetras still want a heater.
- Best tank mates for specific species11 min read
Tank mates for bettas, neon tetras, cherry shrimp, and corydoras — plus the fish that should live alone. Use the compatibility checker before you buy the mix.
- Best fish for beginners10 min read
Hardy freshwater fish for a first cycled tank: neon tetras, corydoras, bristlenose plecos, guppies, cherry shrimp. Not goldfish in a bowl, not a common pleco.
- Best fish for a 10-gallon tank11 min read
What actually fits in a 10-gallon: a betta, a shrimp colony, or a small school of nano fish. Not goldfish, not a common pleco, not a community zoo.