What you can track
- Log every test in seconds — values show green, amber, or red against your target range, the moment you enter them
- Keep your dosing on schedule with countdowns and a tap to mark each dose done
- Track your livestock — corals, fish, inverts — with photos, sources, and how long they've been in your reef
- See every parameter's trend over time, with your target band drawn right on the chart
Prefer paper? Free Printable Reef Tank Parameter Log (PDF) — the same log as a free printable sheet.
Pricing, plainly
Log unlimited parameters and doses, track your full livestock list, and see your trends across weeks and months. Export your own data as a CSV. Nothing core is locked behind a paywall.
7-day free trial. Adds correlation insights and PDF reports. Cancel anytime from your Apple ID settings.
Private by design
Questions
Is Coralog free?
The core app is free, with no account needed. Log unlimited parameters and doses, track your full livestock list, and see your trends across weeks and months. Export your own data as a CSV. Nothing core is locked behind a paywall. Premium ($6.99/month or $39.99/year after a 7-day trial) adds the analysis features.
Where is my data stored?
On your iPhone. Coralog never uploads what you record, and never shares or sells your data — there is no account and no cloud backend. Some apps send anonymous usage counts (no identifiers) so we can see which features get used; each app's privacy policy spells out exactly what, if anything, is sent.
Does Coralog require an account?
No. You can start logging the moment the app opens — there is no sign-up, no email, and nothing to create.