Saltwater & reef care, minus the gatekeeping
You belong on the reef.
Saltwater has a reputation for being expensive, fiddly and experts-only. It isn't — it's more forgiving than people say, once you get the water right. Coralkin helps you start with confidence and grow from your first clownfish to your first coral, in plain, kind language.
No matches — try another word (e.g. a species, “alkalinity”, or a tool).
Browse the care guidesStart with the clownfish →
Every care number fact-checked against marine-aquarist & veterinary sources — never guessed.
- 72fish, corals & inverts
- 26saltwater fish
- 22corals covered
Start with your first fish
The most beginner-friendly saltwater fish we cover — hardy, captive-bred, and forgiving of a new keeper. (We cover 72 fish, corals and inverts in all, from first fish to advanced reef.)
Ocellaris Clownfish
The hardy, captive-bred "Nemo" — the friendliest first saltwater fish there is.
Reef-safe community fish✓ Care guide
Percula Clownfish
The true percula — near-identical to ocellaris, with bolder black outlines.
Reef-safe community fish✓ Care guide
Royal Gramma
A hardy purple-and-gold beauty — peaceful, colourful, and nano-friendly.
Reef-safe community fish✓ Care guide
Firefish Goby
An elegant, peaceful hover-fish with a flame-orange tail — perfect for nano reefs.
Reef-safe community fish✓ Care guide
Yellow Watchman Goby
A charming sand-sifter that forms a famous partnership with a pistol shrimp.
Reef-safe community fish✓ Care guide
Green Chromis
A shimmering blue-green shoaler — one of the cheapest, hardiest ways to add movement.
Reef-safe community fish✓ Care guide
Test, don't guess
Most saltwater trouble comes back to one thing: the water. So we do the reading and the math— turning “what should my alkalinity be?” into a real target, how to test it, and what to do if it's off. No dose-by-vibes folklore, no gatekeeping — just current reef practice, fact-checked before we publish it.
72 of 72 fully sourced — every care number fact-checked before we publish it. We never publish numbers we haven't checked.
No gatekeeping here. Whether you're deciding on your first saltwater fish or staring at a parameter that won't behave — you're welcome, and you belong on the reef.