Coralkin honest saltwater & reef care

🌸 Coral Trouble Card

Green Star Polyp Coral Trouble Card

The one page to have ready when a coral starts to slip. Corals almost never need a vet — recovery is a water-chemistry, light/flow, or pest fix. This walks you through the checks in order. Print it, keep it by the tank.

Black & white saves ink and prints cleanly on any printer.

Not sure it's serious yet? Run the symptom checker or the water-test checker first — many worries turn out to be a husbandry fix.

Coralkin honest saltwater & reef care · coralkin.com
Green Star Polyp — Coral Trouble Card

🔬 There's no vet for corals — diagnose the water & environment

Corals almost never need (or have) a vet. A struggling colony is a chemistry, lighting/flow, or pest problem you fix yourself. Work these Coralkin tools:

📇 Fill this in now

My system
What I'm seeing
Recent changes

🚨 Trouble signs now?

  • Polyps staying closed for more than a few days — usually a recent move, a parameter swing, or detritus on the mat; increase flow and wait.
  • The purple mat lifting/peeling from the rock — re-secure it; it re-attaches readily.
  • It's creeping onto neighbouring corals — trim/peel it back and widen the gap (management, not illness).

🚗 First things to check

✅ Do

  • Test the full parameter set — salinity, alkalinity, calcium, magnesium, nitrate, phosphate and temperature — and compare to targets.
  • Check the lighting and flow at this coral's exact spot.
  • Look for pests and for irritation from aggressive neighbours.
  • Check for recent changes — new livestock, a dosing change, a big water change.

⛔ Don't

  • Don't reach for OTC “cures” or dose blindly.
  • Don't change everything at once — stability matters more than any single number.
  • Don't keep a badly-failing colony next to healthy ones without isolating it or fragging off the healthy tissue.

📋 This coral's targets

Colony / form
An encrusting purple mat studded with neon-green polyps; spreads across any surface it touches.
Lighting
Very adaptable — from dim to bright; a medium ≈150–250 PAR is ideal. One of the least light-fussy corals.
Water flow
Flexible — it does well in moderate-to-strong flow, which also helps keep algae off its mat.
Placement
Anywhere it has a surface to encrust — but on an ISOLATED rock or island, not touching your main rockwork.
Temperature
75–82°F (24–28°C).
pH
8.1–8.4.
Specific gravity
1.023–1.026 (reef-standard ≈35 ppt).
Other targets
Very tolerant of chemistry swings — no dosing needed. Keep it stable.
Feeding
Photosynthetic — no feeding needed; light does the work.
Growth & spread
Very fast and encrusting — it grows over rock, sand, glass and other corals in any direction. Contain it on its own rock with a gap, or it takes over the tank.
Natural range
Indo-Pacific reefs.

🌸 A struggling coral is almost always telling you about its water, light, flow, or a pest — not an infection a vet can treat. Stabilise your parameters to target, confirm the light and flow suit this coral, and rule out pests and aggressive neighbours before changing anything drastic. Sudden swings are themselves a stressor.

❓ Work through

  • Is a parameter off-target?
  • Is the light or flow wrong for this coral?
  • Any pests, or aggressive neighbours?
  • What changed recently?