A 20-gallon aquarium is a sweet spot for many hobbyists. It holds enough water to stay stable, fits on most sturdy furniture, and gives you room for a school of small fish plus a few bottom dwellers. The key is choosing fish that stay small, get along, and suit the...
Every new aquarium goes through a cycle: bacteria colonize rock, sand and filter surfaces and learn to turn toxic ammonia into nitrite, then into less harmful nitrate. In a saltwater tank, fish and invertebrates are especially sensitive to ammonia and nitrite. Cycling...
The pump is the heart of a pond. It drives the filter, the waterfall and the circulation that keeps water oxygenated. Too small and the water stagnates and the filter can’t keep up. Too big and you pay for wasted electricity and may churn the pond into a...
Corals can’t move to find food or shed waste, so the water has to do it for them. Flow brings food and oxygen, carries away waste, and helps keep detritus suspended so the skimmer and filter can remove it. A powerhead (also called a wavemaker) is the main tool...
A power outage turns a balanced aquarium into a still box of water. The filter stops, the heater goes cold and the surface goes flat. Most fish can ride out a few hours without trouble, but a long outage can kill fish and the bacteria that keep the water safe. A...
