ReefCadence: Reef Tank Log

**Free. All of it. Forever.** Every feature in ReefCadence is unlocked for everyone. Unlimited tanks, unlimited tasks, unlimited parameters, unlimited measurements, several a day if you want. No account, no sign-in, no ads, no tracking, and no network connection required. It works from a cold launch in Airplane Mode. **It works out what your tank eats.** Every log app can store the number 8.2 and draw a line through it. ReefCadence answers the question you actually ask at the tank: given what my tank consumed this week, how much of my bottle do I add today? It builds a dose-adjusted series from your own timestamped tests, taking every measurement and subtracting the alkalinity added by every dose you logged or your pump accrued on its nightly schedule. It fits a least-squares line through the last 14 days rather than differencing two adjacent tests, because a Hanna checker's published accuracy is around 0.7 dKH at reef levels and a 12-hour difference is mostly instrument noise. Then it tells you the truth about the answer: "1.1 plus or minus 0.2 dKH/day, from 6 tests over 13 days", with the scatter and the fitted line on screen. Never a fake-precise 1.134. **And it tells you when that changes.** Corals grow. Uptake climbs every month. Most reefers find out when alkalinity sags and SPS tips burn. Dose Drift Watch compares this fortnight's demand to the last and sends one local notification: "Alk demand rose 22% this month, 0.9 to 1.1 dKH/day. Raise your daily dose from 15 mL to 18 mL." It only fires when the move is both material and larger than the error bar, because a notification you cannot trust is worse than none. **Everything else, done properly.** • Unlimited charts with shaded target bands, 7d/30d/90d/1y/all ranges, and tap-to-scrub. Dose and water-change markers sit on the same timeline, so every dip is explained. • Quick Test: one sheet, one hand, wet fingers, under twenty seconds. Your last value shown as a hint on every field. • Dose ledger with one-tap repeat, plus standing pump schedules that accrue automatically and are visibly marked, so you always know which numbers the app assumed. • Around 18 supplement products with the source of every constant printed on screen. Liquids, dry recipes (anhydrous and dihydrate calcium chloride listed separately, because they differ by a third by mass) and rate products. Add your own from the label. • Correction doses split across days at a safety cap, with each day adding that day's maintenance dose on top, so a three-day fix actually lands on target instead of below where it started. That arithmetic mistake is the one that quietly kills coral. • Honest net water volume: display plus sump plus frag, minus rock and sand displacement. Nameplate volume overstates by 10 to 20 percent, and every dose is wrong in proportion. • Water change and salt mix calculator with a dilution preview for every parameter, and a Calibrate flow that back-solves your brand's constant from what you actually weighed. • One global units toggle: US gallons or litres, Fahrenheit or Celsius, dKH or meq/L or ppm CaCO3, ppm PO4 or ppb PO4-P, ppm NO3 or NO3-N, ppt or specific gravity. Storage stays canonical metric, so switching units never touches a stored value. • Reliable local reminders, budgeted against the iOS 64-notification limit and rebuilt every launch soonest-due-first, so they never silently vanish. **Show the math.** Every computed number has a "Show the math" disclosure printing the fully substituted equation with your real values, and the cited source of every product constant. Nothing is a magic result. Guidance only: this is arithmetic on your own numbers and published product constants, to be verified against your test kit and the manufacturer's instructions. Not chemistry advice. TERMS & PRIVACY Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://jcreates.dev/privacy/reefcadence