Where to Place a Heater for Even Temperature
Same heater, same wattage, same dial setting: move it twenty centimetres and a long tank can lose most of its gradient.
equipment
3 guides
CO2 Diffusers vs Reactors Compared
Dissolution rates, working pressure, flow penalty and running cost for five ways of getting carbon dioxide into aquarium water.
Aquarium Heater Wattage: A Sizing Guide
Room temperature, not tank volume, decides how many watts you actually need, and the old per gallon rule gets it badly wrong.