Problem checks

Reef tank guides

Find the answer, check the sizing, and plan your next step. Browse by topic or search for your tank.

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Equipment · 10 min read

Reef tank equipment list for a stable first build

A practical reef tank equipment list that separates must-have gear from optional upgrades before the first cart gets expensive.

water gallons x 8.3 lb, then add rock, sand, stand, and gear
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Budget · 9 min read

How much does a reef tank cost?

Estimate reef tank startup cost by tank size, reef goal, equipment tier, hidden consumables, and the first 90 days.

real budget = startup cart + first-90-day supplies + repair cushion
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Return Pump · 8 min read

What size return pump do I need for a reef tank?

Size a reef tank return pump by real GPH after head loss, overflow limits, noise, and sump turnover instead of box rating alone.

system gallons x 5 to 10 = target delivered GPH
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Tank Format · 9 min read

AIO vs sump reef tank: which should beginners choose?

Compare all-in-one and sumped reef tanks by setup difficulty, upgrade path, noise, equipment space, cost, and beginner risk.

simpler setup + smaller footprint - equipment room
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Skimmer · 7 min read

Is my protein skimmer too small?

Check whether your skimmer rating has enough headroom for your tank volume, reef goal, and bioload before you buy or upgrade.

display gallons x 1.5
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Flow · 8 min read

How much flow does a reef tank need?

Calculate a practical flow target for soft coral, LPS, mixed reef, and SPS systems without confusing return-pump turnover for coral flow.

display gallons x 10
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Lighting · 8 min read

Is my reef lighting strong enough?

Check reef lighting by coral goal, PAR target, and footprint coverage instead of picking a fixture from tank gallons alone.

tank length x tank width <= total fixture coverage
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Heating · 7 min read

Reef tank heater size and safety check

Size reef tank heaters with enough wattage to hold temperature without creating a dangerous stuck-on failure risk.

display gallons x 2.5
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Build Check · 9 min read

Check your reef build before buying

A pre-buy reef tank checklist for catching weak gear, missing essentials, and expensive mismatches before checkout.

display gallons x 1.5, 2.0, or 2.5
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Water Chemistry · 8 min read

How long does a reef tank take to cycle?

A practical reef cycling timeline that separates ammonia processing, testing confidence, and stocking readiness.

Readiness = ammonia 0 + nitrite 0 after the tank processed a known ammonia source
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Water Chemistry · 8 min read

How to lower nitrates in a reef tank without shocking livestock

Lower reef nitrate with feeding control, water changes, export capacity, and patient trend tracking.

Nitrate trend = nutrient input - nutrient export
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Water Chemistry · 8 min read

How to lower phosphates in a reef tank safely

Reduce reef phosphate without stripping nutrients too quickly or destabilizing corals.

Phosphate pressure = food input + source water + detritus release - export
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Troubleshooting · 8 min read

Reef tank algae problems: find the cause before buying a cure

Diagnose common reef algae causes by light, nutrients, source water, flow, stocking, and maintenance.

Algae pressure = available nutrients + light + surfaces + weak export
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Troubleshooting · 8 min read

Cyano vs dinos in a reef tank

Tell cyano and dinoflagellates apart before changing nutrients, flow, lighting, or treatment strategy.

Risk = misidentification x treatment strength
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Equipment · 8 min read

ATO setup guide for reef tanks

Set up an auto top off system around salinity stability, reservoir size, sensor safety, and failure modes.

Reservoir days = reservoir gallons / daily evaporation gallons
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Equipment · 8 min read

Reef controller setup guide for useful safety

Use a reef controller for real safety: heater cutoff, alerts, pump control, and monitoring without replacing husbandry.

Controller value = monitored risk + reliable alert + controlled response
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Maintenance · 8 min read

How to maintain reef tank filters without causing a nutrient spike

Clean reef mechanical, chemical, and biological filtration on a schedule that protects stability.

Mechanical media value drops when trapped detritus decomposes
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Water Chemistry · 8 min read

RODI water for reef tanks

Plan RODI water around source-water risk, filter stages, storage, TDS checks, and algae prevention.

RODI readiness = clean source + maintained filters + clean storage
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Water Chemistry · 8 min read

Reef tank salinity stability

Keep reef salinity stable with ATO, calibrated testing, RODI water, and water-change discipline.

Evaporation removes water but leaves salt behind
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Water Chemistry · 8 min read

Reef tank alkalinity stability

Plan alkalinity testing, demand tracking, water changes, and dosing without chasing daily noise.

Daily demand = yesterday alkalinity - today alkalinity after accounting for dosing
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Water Chemistry · 8 min read

Reef tank dosing for beginners

Start reef dosing only after testing shows repeatable demand from coral growth.

Dose need = measured daily consumption - water-change replacement
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Maintenance · 8 min read

Reef tank water change schedule

Choose a reef water-change schedule based on tank size, nutrient trend, dosing demand, and stability.

A water change reduces dissolved pollutants roughly by the changed percentage
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Livestock · 8 min read

Where to place corals in a reef tank

Place corals by light, flow, aggression, growth shape, and room for future colonies.

Placement fit = PAR band + flow band + aggression space + maturity
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Livestock · 8 min read

Stocking order for a beginner reef tank

Build a beginner stocking order around cycling, aggression, bioload, maturity gates, and coral readiness.

Bioload pace = new livestock load <= export and bacteria margin
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Livestock · 8 min read

Cleanup crew for a reef tank

Size a reef cleanup crew by tank maturity, algae type, food availability, and compatibility.

Cleanup crew need = available food + tank footprint + algae type
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Disease · 8 min read

Quarantine reef fish for beginners

Plan beginner fish quarantine around observation, ammonia control, stress reduction, and display protection.

QT readiness = biological filter + oxygen + temperature + observation time
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Disease · 8 min read

Marine ich in a reef tank

Understand marine ich response options, quarantine limits, display fallow planning, and why reef-safe shortcuts fail.

Display risk = exposed fish + parasite life cycle + stress
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Livestock · 8 min read

When can I add an anemone to a reef tank?

Decide anemone readiness by tank maturity, light, flow, pump protection, and stability history.

Anemone readiness = maturity + stable light + stable flow + protected pumps
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Tank Format · 8 min read

Choosing your first reef tank size

Choose a first reef tank size by stability, budget, equipment fit, floor load, and livestock ceiling.

Filled water weight starts around gallons x 8.3 lb
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Lighting · 8 min read

Reef tank lighting explained for beginners

Understand reef lighting by PAR, coverage, spread, spectrum, schedule, and coral goal before buying LEDs.

Coverage target = tank length x tank width
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Flow · 6 min read

Where to place wavemakers in a reef tank

Start with an open path across the tank, then adjust pump position to the rockwork, sand and coral response. These layouts give you a starting point to test.

Combined pump GPH ÷ display gallons
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Flow · 8 min read

Flow requirements for SPS, LPS, and soft corals

Plan flow zones for SPS, LPS, and soft corals without treating the whole tank as one average number.

Soft/LPS planning band = roughly 10-30x turnover
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Maintenance · 8 min read

Reef tank maintenance schedule for beginners

Build a reef maintenance schedule for daily observation, weekly testing, water changes, filter cleaning, and monthly gear checks.

Maintenance interval shortens as feeding, bioload, and coral demand rise
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