https://reefnotes.com/en/guides/ Practical aquarium guides on water tests, dosing, water changes, the nitrogen cycle and more — from reefnotes. en Thu, 21 May 2026 12:00:00 GMT https://reefnotes.com/en/guides/first-30-days-freshwater/ https://reefnotes.com/en/guides/first-30-days-freshwater/ Thu, 21 May 2026 12:00:00 GMT What actually happens in the water column from setup day to first stable readings — and how to stop the standard new-tank mistakes from killing fish. https://reefnotes.com/en/guides/nitrogen-cycle-plain-language/ https://reefnotes.com/en/guides/nitrogen-cycle-plain-language/ Thu, 21 May 2026 12:00:00 GMT The chemistry of how fish waste becomes plant fertiliser, why the order matters, and what "the tank is cycled" actually means under the hood. https://reefnotes.com/en/guides/co2-without-a-meter/ https://reefnotes.com/en/guides/co2-without-a-meter/ Fri, 15 May 2026 12:00:00 GMT A two-number CO₂ check that works for any planted tank. The chemistry behind the table, the cases where it lies, and the dropchecker question.