Troubleshooting8 min readReviewed 2026-05-01
By Max Rodes for ReefCrafter. Reviewed against the rule engine and 3 sources.

Cyano vs dinos in a reef tank

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

A mature reef aquarium with corals under bright reef lighting.

A mature reef makes the planning problem obvious: light, flow, livestock, and equipment all have to agree with each other.

Image: Dieter Karner, CC BY 2.0, via Wikimedia Commons
Direct answer

Cyano and dinos can look similar, but they reward different responses. Identify texture, bubbles, daily pattern, nutrient context, and microscope confirmation if possible before blackouts, dosing, or aggressive nutrient changes.

What I would check first

The question I want this page to answer is simple: what would make me regret this cart in three months? If the answer is light spread, weak flow, a risky heater, or missing RODI/testing, fix that before checkout.

Quick check

  1. 1Do not start a treatment plan from color alone.
  2. 2Check whether nutrients are too high, too low, or swinging.
  3. 3Improve flow and detritus removal before chemical escalation.
  4. 4Protect corals and oxygen levels during any blackout or treatment.

Run the connected calculator

This guide's rule math is available as an interactive check. Adjust gallons, goal, tier, and bioload, then pass the result into the planner.

Skimmer target
150 gal rating

Light, medium, and heavy targets are 113, 150, and 188 gallons of skimmer rating.

Heater safety band
190-375 W

Use two heaters around 95 W each, preferably controller-backed.

Display flow
2,250 GPH

The 20-40x band gives 1,500-3,000 GPH before aquascape and pump placement.

Return pump rating
750-1,500 GPH

That aims to deliver 375-750 GPH after about 50% plumbing loss.

Light coverage
864 sq in

For this goal, use the 150-250 PAR band and cover the full 864 sq in footprint.

Startup budget
$3,500-$5,575

Monthly consumables often land around $60-$120 before livestock surprises or upgrades.

The math, in plain English

Skimmer check

Sizing rule
display gallons x 1.5, 2.0, or 2.5

Example: 75g mixed reef x 2.0 = 150g skimmer rating target.

The multiplier follows bioload so a fish-heavy build does not get the same filtration margin as a light soft-coral tank.

Flow check

Sizing rule
display gallons x 10, 20, or 40

Example: 75g mixed reef x 20 = 1,500 GPH useful display flow.

This catches underpowered display movement before dead spots become algae and detritus problems.

Heater check

Sizing rule
display gallons x 2.5 to 5.0 total watts

Example: 75g tank = about 188W to 375W total heater wattage.

The band balances temperature stability against stuck-on heater risk.

Return check

Sizing rule
system gallons x 5 to 10 after head loss

Example: 95g system = 475 to 950 GPH delivered return flow.

This keeps sump turnover practical without asking the return pump to do every flow job in the display.

Rule shorthand
  • Risk = misidentification x treatment strength
  • Low nutrients plus bright light often changes the dino risk picture
  • Flow and export change both cyano mats and detritus buildup

Keep the decision connected

What pest identification really means

Cyano vs dinos in a reef tank is a system decision, not an isolated fact. ReefCrafter ties the answer back to tank size, livestock pressure, equipment margin, and the failure mode most likely to punish the build.

How to make the decision

Start with the observable result, then check the surrounding inputs. If the plan depends on pest identification, confirm the tank, gear, and routine can support it before buying another product or animal.

  • Do not start a treatment plan from color alone.
  • Check whether nutrients are too high, too low, or swinging.
  • Improve flow and detritus removal before chemical escalation.
  • Protect corals and oxygen levels during any blackout or treatment.

When to slow down

Slow down when the fix would hide wrong-treatment escalation. A reef tank usually improves faster when the root cause is removed than when the symptom is forced to disappear.

Common mistakes

  • Treating pest identification as a one-product problem.
  • Ignoring wrong-treatment escalation because the tank looks acceptable today.
  • Changing several variables at once and losing the ability to see what helped.
  • Using a generic recommendation without checking tank size, livestock, and equipment margin.

Buying/spec checklist

  • The relevant calculator or guide has been checked before purchase.
  • The plan fits current livestock and the next realistic livestock step.
  • The maintenance routine can support the choice after the first week.
  • The product or animal has a clear job in the build.

ReefCrafter may earn a commission when vendor links are used. The check comes first: recommendations should follow the build requirements, not the affiliate program.

FAQ

Can the planner replace observation?

No. ReefCrafter catches sizing, compatibility, and planning risk. Daily animal behavior, test trends, and equipment condition still decide whether the tank is actually stable.

Should beginners fix this with a product first?

Usually no. Identify the cause, confirm the measurement, and then decide whether husbandry, stocking pace, or equipment is the right fix.