Controllers · Hanna Instruments

Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC fit check

Quick answer

Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC is a phosphorus checker from Hanna Instruments. Listed features: Handheld colorimeter for marine phosphorus, ppb scale; Range 0-200 ppb, resolution 1 ppb; Accuracy +/-5 ppb +/-5% of reading. Confirm current specs on the retailer listing before buying.

Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC: best for systems 5 gallons and up. Specs, compatibility math, sizing risks, and…

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Who it is for

Good fit for

✓ Keepers who test this parameter on a schedule and want a numeric reading instead of color-matching.

Not a fit for

✕ A first purchase before the heater, ATO, and maintenance routine are stable.

Listed features

Handheld colorimeter for marine phosphorus, ppb scale
Range 0-200 ppb, resolution 1 ppb
Accuracy +/-5 ppb +/-5% of reading
LED light source at 525 nm
1 AAA battery, reagent included

Specs checked against bulkreefsupply.com.

Compatibility math

Build role

gear value = risk reduced + maintenance made easier + build fit

Example: Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC belongs in the plan only if it solves a real stability or maintenance job.

ReefCrafter keeps optional upgrades behind core stability requirements.

Risk notes

Automation can add complexity if the basic heater, ATO, and maintenance plan are not already stable.

Professional fit context

Check probe support, controllable outlets, alerting, redundancy, and setup complexity.
Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC best for systems 5 gallons and up; confirm that range against the final display volume, sump volume, and livestock plan.

Alternatives to compare

Hanna Instruments HI758 Marine Calcium Checker HC
Budget-tier alternative in the same category.
Hanna Instruments HI772 Marine Alkalinity (dKH) Checker HC
Budget-tier alternative in the same category.
Hanna Instruments HI774 Marine Phosphate Ultra Low Range (ppm) Checker HC
Budget-tier alternative in the same category.

Full spec snapshot

Category: Controllers
Build tier: Budget
Estimated price: $75
Tank fit range: best for systems 5 gallons and up
Format: Phosphorus Checker

Questions

What should I compare the Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC against?

Hanna Instruments HI758 Marine Calcium Checker HC (Budget-tier alternative in the same category); Hanna Instruments HI772 Marine Alkalinity (dKH) Checker HC (Budget-tier alternative in the same category); Hanna Instruments HI774 Marine Phosphate Ultra Low Range (ppm) Checker HC (Budget-tier alternative in the same category).

What range and accuracy does the Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC list?

The retailer listing gives: Handheld colorimeter for marine phosphorus, ppb scale; Range 0-200 ppb, resolution 1 ppb; Accuracy +/-5 ppb +/-5% of reading.