Coralkin honest saltwater & reef care

🌸 Coral Trouble Card

Duncan Coral 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
Duncan Coral — 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 or shrunken — usually too much flow (move it lower/calmer) or a chemistry swing.
  • Not extending feeder tentacles at feeding time — check flow and water quality.
  • Receding flesh / bare skeleton — an alk/Ca swing; stabilise chemistry.

🚗 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
Clusters of round, daisy-like polyps on a branching skeleton; adds new heads readily, so a 1–2 head frag becomes a showpiece.
Lighting
Low-to-moderate — about 50–150 PAR; not fussy.
Water flow
Low — bottom or sand, gentle flow. In high flow it won't open well or catch food.
Placement
Lower rock or the sand bed in a calmer, lower-flow spot; leave the upper high-light zones for other corals.
Temperature
75–82°F (24–28°C).
pH
8.1–8.4.
Specific gravity
1.023–1.026 (reef-standard ≈35 ppt).
Other targets
LPS build a stony skeleton — keep alkalinity (≈8–11 dKH), calcium (≈400–450 ppm) and magnesium (≈1300–1450 ppm) stable.
Feeding
Photosynthetic AND an eager hunter — it loves meaty foods (brine, mysis, cyclops, small shellfish). Feed once or twice a week for noticeably faster growth.
Growth & spread
Fast, especially when fed — it keeps adding heads, so a small frag fills out into a big colony over time.
Natural range
Indo-Pacific, including Australian waters.

🌸 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?