Greg Carroll’s 16 Reefing Tips for First Time & Advanced Reefers.
Practical, No‑Nonsense Advice
If you want one shortcut to avoid the mistakes Greg has made over 26 years in the hobby, this is it. Below are the core lessons Greg wishes someone had given him on day one. Greg speak from experience: setups that look great are the result of discipline, time and a few hard lessons. Read this, follow a few of the fundamentals, and the hobby will become a whole lot more enjoyable!
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1. Patience — the ugly word that matters
Patience is the single hardest thing for new reefers. Instant gratification is real: you see a beautiful tank and want the same in your living room yesterday. Don’t rush the process. A reef is an ecosystem you build by steps, not a display you turn on and hope for the best.
Practical steps:
Cycle the tank before full lights or corals — let microbes find balance first.
Delay full lighting if possible; low or no lights for the first weeks keeps slime and macroalgae from exploding.
If algae outbreaks begin, try the simplest reset first: turn the lights off for a short blackout.
2. Resilience — expect problems and stay in it
Reefing is challenging on purpose. If you love a craft and learning, you will enjoy the problems. If you expect it to be trivial, this hobby will frustrate you. Embrace the setbacks; they are how you get better. Also, don’t be ashamed of mistakes — many of us have been there but few publicize it.
3. Consistency — pick a path and stick to it
Don’t tinker constantly. If your tank is doing well, keep doing what got it there. Water changes, feeding schedule, maintenance rhythm — these build success. The “one weird trick” crowd or constant switching between dosing methods will likely create instability.
4. Build and maintain a cleanup crew throughout
Cleanup crew animals (snails, hermit crabs, small grazers) are vital. Add them gradually as you add fish or increase bioload — do not dump a huge package into a brand new tank. If you put too many grazers in before enough algae exists, they will starve, die, and create nutrient spikes that fuel the very problem you tried to prevent.
Practical rule: when you add fish or increase feeding, add a handful of cleanup crew animals. Replace losses as the system ages.
5. Reefing is as hard as you want to make it
There are reef tanks that are simple and beautiful, and there are tanks that are complex, highly tuned experiments. Soft corals and LPS are much more forgiving. SPS is the pinnacle and demands stability, high light, flow and careful chemistry management. Decide what you want before you pick methods and equipment.
6. Be careful which problems you try to solve
Every system choice has tradeoffs. Carbon dosing can lower nutrients but usually works in tandem with skimming and mechanical export. Two part dosing solves alkalinity/calcium issues, but raises salinity. ICP methods remove water changes but add complexity. GFO beats algae but starves coral. Know what problem you actually have before adding a complex solution.
7. Don’t blindly copy the crowd — pick someone to emulate
Crowdsourcing a dozen opinions leads to confusion. Instead, find one successful person or trusted source doing what you want to achieve and follow their method. Learn the why behind their choices. If you are new, books like The Reef Aquarium (volumes by Julian and Charles) give technical grounding. If you follow a content creator or store, pick someone accessible who can help clarify details.
8. Pick corals deliberately — fit them to your lifestyle
Match coral selection to your time, budget and tolerance for maintenance. If you want a tank that looks great but easy, soft corals will get you there quickly. Soft corals are forgiving, grow fast, and are inexpensive. If you want the SPS challenge, commit to the chemistry, flow and lighting needed to keep them happy. SPS are demanding and expensive.
9. One good mentor beats many piecemeal opinions
Find a reliable mentor, local store or a creator whose results you like. They should have reproducible success and be willing to explain why they do certain things. Avoid forum pile-ons where answers are inconsistent and often recycled without real experience.
10. The hobby is as affordable as you make it
You can spend a fortune or you can be very reasonable. Core life support, a reliable return pump, decent lighting and quality plumbing is where your money gives the best returns. But you do not need the most expensive gadget for your first tank. Consider:
Buying used systems or parts to cut initial costs drastically.
Starting with soft corals to grow the display affordably.
Choosing equipment that is reliable rather than feature laden when you are new.
11. Color and lighting — how to get that pop
Fluorescence is the wow factor. Corals absorb certain wavelengths (usually blue/violet) and reemit different colors. Two key points:
Spectral peaks matter. Royal blue and violet channels drive fluorescence. If you want that fluorescent orange or pink pop, make sure your light has those wavelengths.
Use a small blue flashlight in the store when shopping for corals. If a frag lights up under blue, that frag will flash bright color in your tank too.
Additional tips:
High PAR can increase color and growth, but it also increases risk. If you ramp PAR, make sure flow and nutrition match the coral needs.
Placement experiments help: clip a frag and move it higher or lower to compare growth and color under different light intensities.
White light shots and blue light shots both have value. Many tanks look stunning in white light but Instagram popularized the deep blue look.
12. Growth tips — how to turn a frag into a colony
There is no magic. Give the frag the environment it likes, then leave it alone. Stability is the number one growth booster. Important factors:
Light, flow and placement relative to neighbors. Many frags prefer slightly lower light at first. If a frag struggles, try lower light and gentler flow.
Don’t keep changing light settings. Frequent spectrum and intensity changes force corals to repeatedly adapt and slow growth.
Start with captive raised or farmed corals when possible; they are often hardier.
13. Algae: prevention, common sense, and hammer tools
Algae is a normal part of most systems. Avoid big outbreaks by staying on top of prevention, then escalate carefully:
Prevention: steady cleanup crew, appropriate light levels (more light = more growth), routine water changes and good flow to prevent deposits in dead spots.
Manual removal: siphon, scrub, or use a thumb‑sized siphon tip trick to extract patches off the rock rather than letting them decay in place.
Biological control: herbivorous fish (tangs, foxfaces, some blennies) often outperform invertebrates for grazing in many tanks. Choose species appropriate to tank size and research their long-term care and rehoming needs.
When prevention and manual methods fail, consider targeted tools:
Lower light or reduce photoperiod for a time.
Blackouts for a short period can reset some algae types.
Hydrogen peroxide spot treatments are useful for localized macroscopic infestations; use carefully and avoid directly treating corals without research.
Products like fluconazole (reflux) are effective against bryopsis in many cases, but they should be used with caution and knowledge of their effects.
14. Slimes — what they are and how to beat them
Slimes are often confused: cyano (red/purple), diatoms (brown film), and dinoflagellates (dinos) are distinct. Diagnosis matters because the best fixes differ.
Cyano: often spotty patches; can respond to red slime removers, blackouts, or flow changes.
Diatoms: classic brown film in new tanks; usually pass as silica sources are exhausted.
Dinos: more stubborn. If red slime remover and blackout do not fix it and it keeps returning, consider more aggressive interventions.
Hands‑on treatments that have produced consistent results for many reefers:
Red slime remover products and chem cleaners that target cyanobacteria can remove outbreaks quickly in otherwise healthy systems.
Hydrogen peroxide sprays and controlled exposures can clear heavy infestations when applied carefully.
Introduce biodiversity: adding true live sand or live rock seeded in natural ocean water (examples: live rock that has seeded in the ocean, or microbiome-rich sand) often reintroduces predators and competitors that reduce slime problems long term.
Note on "miracle" products: some algicides do work fast but carry controversy. If you use them, understand the ingredients and risks, and evaluate whether the tank is otherwise healthy enough to survive an aggressive treatment.
15. What will nuke your tank instantly? Heater failures
The single most dangerous equipment to your livestock is the heater. Cheap aquarium heaters are not engineered for the heavy demands of an expensive reef setup. Common failure modes are:
Stuck on: will cook the aquarium rapidly.
Stuck off: cold water can slowly kill livestock without obvious immediate signs.
How to protect yourself:
Replace cheap heaters yearly if you can only afford a basic unit.
Use a heater controller or secondary thermostat that shuts heaters off if temperatures go out of range.
Consider redundancy: two smaller heaters rather than one large heater so one failure does not immediately lose control.
16. What will slowly deteriorate your tank? Complacency and skipping maintenance
Most tanks die slowly, not suddenly. The number one slow killer is complacency. Skipping water changes, neglecting filter socks, postponing routine maintenance — those small cuts add up.
If a water change noticeably improves your tank, that is a sign something was drifting. Water changes are the simplest, most reliable reset. For beginners, regular water changes are the single most powerful habit you can build.
Actionable checklist for new reefers
Decide what you want: softy tank, mixed, or SPS. Match equipment and effort to that target.
Pick one reliable mentor, a trusted local store, or a well-documented method and follow it for your first year.
Cycle your tank, start with lower light, add cleanup crew gradually as you add bioload.
Do regular water changes. Treat them like cleaning a pet's litter — nonnegotiable maintenance.
Protect your heater: change annually or add a controller/redundancy.
Monitor for algae early and respond: manual removal, flow changes, and if needed targeted treatments.
Buy used systems or focus on affordable corals (soft corals) if budget matters.
Final thoughts
Reefing is rewarding because it is an intersection of art, biology and engineering. The challenge is part of the hobby. Start simple, be deliberate, pick a mentor, and stick to the basics — patience, consistency, and maintenance. If you do those things, your chances of success skyrocket. When you are ready to level up, learn the why behind more advanced methods instead of collecting a hundred half-understood tips.
Quick mantra to remember: patience + consistency + water changes = a sturdy reef foundation.
If you take one thing from this list, make it this: protect your heater and your maintenance routine. Everything else is easier to fix if those are in place.
Acknowledgments
Thank you to Greg Carroll for sharing his knowledge with the SR community. Greg does a live most mornings on his instagram channel HERE
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