Corals are the heart of a reef aquarium, but they need stable conditions to thrive. This guide covers everything a beginner needs to know to keep corals successfully.
Start with Soft Corals
Soft corals are by far the most forgiving for beginners. They tolerate a wider range of lighting and flow, and they're more resilient to parameter swings. Great starter corals include:
- Mushroom corals (Discosoma) — nearly bulletproof, come in amazing colours
- Zoanthids and Palythoa — colourful, fast-growing, and hardy
- Kenya Tree corals — grow quickly and tolerate low light
- Toadstool leathers — impressive size, easy to keep
- Green Star Polyps (GSP) — vivid green, spreads across rockwork
Once you're comfortable with soft corals, you can move to LPS (Large Polyp Stony) corals like Hammer corals, Torches, and Frogspawn. These need slightly more attention to alkalinity and calcium levels.
Lighting
Corals are photosynthetic — they rely on light to feed. Most soft corals and LPS do well under moderate LED lighting (100–200 PAR). SPS corals need much higher light (300+ PAR), but those are an advanced topic.
Set your lights on a timer: 8–10 hours of full intensity per day. Ramp up and down over 30–60 minutes to simulate sunrise and sunset. Add a blue/actinic period before and after the main photoperiod to bring out fluorescent colours.
Water Flow
Corals need water movement to deliver food, remove waste, and prevent detritus from settling on them. Soft corals generally prefer moderate, indirect flow. LPS corals like gentle to moderate flow — too much direct current can damage their flesh.
Use wavemakers on a random or pulse mode rather than a constant stream. This mimics natural reef conditions.
Water Parameters
For coral keeping, consistency matters more than hitting exact numbers. Aim for:
| Parameter | Target |
|---|---|
| Temperature | 25–26°C |
| Salinity | 1.025–1.026 sg |
| pH | 8.0–8.3 |
| Alkalinity | 7–9 dKH |
| Calcium | 400–450 ppm |
| Magnesium | 1250–1350 ppm |
| Nitrate | 5–15 ppm |
| Phosphate | 0.03–0.10 ppm |
Test weekly and keep a log. Sudden changes — even toward "ideal" numbers — stress corals more than slightly off but stable values.
Feeding
Many corals get most of their nutrition from light, but supplemental feeding helps them grow and colour up. Broadcast-feed with phytoplankton or coral-specific foods like Reef-Roids once or twice a week. Target-feed LPS corals with small meaty foods using a turkey baster.
Common Mistakes
- Adding corals too soon — wait until your tank is mature (3+ months)
- Chasing perfect numbers — stability beats perfection
- Too much light too fast — acclimate new corals by starting with reduced intensity
- Overstocking — corals need space and will sting neighbours if too close
- Neglecting water changes — 10% weekly keeps nutrients balanced