Reef Tank Startup 90 Day Plan: Cycle to First Coral

Rushing the first three months is the single most common reason new reefers lose livestock and give up. A disciplined reef tank startup 90 day plan takes the guesswork out of the process by tying each decision to the biological clock of your system rather than your patience. This guide from Gensou Aquascaping at 5 Everton Park, Singapore walks through the full timeline from dry rock and salt mix to your first coral frag. The milestones below assume a typical 200-400 litre display with a sump, protein skimmer, and LED lighting.

Quick Facts

• Total timeline: 90 days from filling to first coral, with optional extension for SPS
• Cycle window: days 1-30, no livestock beyond ammonia source
• Cleanup crew added: around day 35 once nitrites read zero
• First quarantined fish: day 45-60 after a stable nitrate curve
• First soft coral or easy LPS: day 75-90 with stable alkalinity
• Target parameters at stocking: SG 1.025, 25-26 °C, dKH 8-9, NO3 5-10 ppm
• Budget guide in Singapore: $1,500-3,000 for full startup excluding display tank

Week 1-2: Setup and Rock Aquascape

Mix RODI water with reef salt to SG 1.025 and let it circulate for 24 hours before testing. Dry rock goes in next — epoxy and cable-tie the structure so there is open flow behind every rock, which prevents the detritus pockets that fuel nuisance algae later. Install your return pump, skimmer (left dry), heater set to 26 °C, and at least one powerhead for circulation. Do not run the skimmer yet; it has nothing to remove.

Add an ammonia source on day 3 — Dr Tim’s Ammonium Chloride dosed to 2 ppm is the cleanest option, and a bottled bacteria starter like Microbacter7 accelerates colonisation. Test ammonia and nitrite daily from here.

Week 3-4: Cycle Completion

By day 14-18 ammonia should be falling and nitrite spiking. Re-dose ammonia to 2 ppm once you see the first drop — a healthy cycle can process this overnight by day 25. The cycle is complete when both ammonia and nitrite read zero within 24 hours of a 2 ppm dose. Do a 25 percent water change at day 30 to knock nitrate down below 10 ppm and switch the skimmer on with a wet skim.

Week 5-6: Cleanup Crew and Parameter Logging

Add a conservative cleanup crew around day 35: five to ten Trochus or Nassarius snails per 100 litres plus a handful of hermit crabs. Singapore shops around Pasir Ris Farmway stock these reliably. Begin a daily log of alkalinity, calcium, magnesium, and nitrate — you want to see how fast the bare system drifts so that dosing later is targeted, not guessed.

Week 7-8: First Fish

Days 45-60 is the window for the first one or two fish, ideally quarantined in a separate 40 litre tub for at least four weeks on prophylactic copper or tank-transfer method. A pair of ocellaris clowns or a single royal gramma are forgiving first choices. Feed lightly, twice a day, and watch nitrate rise — it should settle between 5 and 15 ppm if the skimmer is tuned correctly.

Week 9-10: Stabilisation and Second Fish

Introduce a second quarantined fish only if the first is eating and nitrate has not spiked above 20 ppm. Dose two-part or kalkwasser if alkalinity drops below 8 dKH — although with no coral yet, consumption is minimal. Start weekly 10 percent water changes with properly mixed, temperature-matched salt water.

Week 11-12: First Coral

Day 75-90 is the earliest sensible window for coral. Start with tough, forgiving species: green star polyp, Kenya tree, Zoanthids, or a small Duncan frag. Dip every coral using the protocols outlined in our coral dipping guide, and acclimate lighting by starting at 30-50 percent intensity. Do not add SPS in the 90 day window — nutrient stability typically needs six months of tracked data first.

Common Pitfalls to Avoid

Impatience causes more crashes than bad equipment. Skipping quarantine introduces ich and velvet that force 76-day fallow resets. Overstocking cleanup crew starves them once detritus is gone, and they die, restarting the cycle. In Singapore’s ambient 30 °C rooms a chiller rated to pull the tank to 25 °C is non-negotiable — heat stress alone will stall a cycle and bleach corals within days.

Related Reading

• Live Rock vs Dry Rock Cycling: Pros, Cons, Timeline
• Marine Nitrogen Cycle vs Freshwater
• Quarantine Copper Treatment Protocol
• Marine Aquarium Equipment Checklist
• Saltwater Aquarium Cost Breakdown Singapore