Shiwa Crisul

Shiwa Crisul is your dedicated companion for marine reef and freshwater planted tank keeping. Log water parameters, track trends over time, and know exactly when and how to dose — all in one beautifully designed app built for serious hobbyists. Track the parameters that matter most. For reef tanks: alkalinity, calcium, magnesium, nitrate, phosphate, potassium, salinity, temperature, and pH. For planted freshwater tanks: pH, carbonate hardness, general hardness, nitrate, phosphate, potassium, iron, temperature, and estimated CO2. Every reading is stored locally on your device and never uploaded to the cloud. Dive deep into your data. The trends screen shows a 14-, 30-, or 90-day chart for any parameter, complete with a regression trend line, stability score, daily consumption rate, and a forecast of when your levels are expected to leave their target band. The built-in dosing calculator tells you exactly how many grams or milliliters of a specific compound you need to bring any parameter back on target, with optional split-dosing across multiple days to stay within safe daily change limits. Manage your livestock with confidence. The species compatibility engine covers dozens of marine fish, corals, invertebrates, and freshwater species, flagging aggression, territorial, dietary, and chemical compatibility issues before they become costly problems. Maintain multiple tanks, set custom target ranges per tank, and attach notes and photos to any test session.