Controllers · Focustronic

Focustronic Mastertronic Automated Water Tester fit check

Quick answer

Focustronic Mastertronic Automated Water Tester is an automated multi-parameter tester from Focustronic. Listed features: Standalone automated tester for Alk, Ca, Mg, NO3, PO4 and organics; High-precision stepper/DC pumps + colorimetric photosensor; WiFi with iOS/Android app. ReefCrafter's catalog fit range is 20+ gallon systems.

Focustronic Mastertronic Automated Water Tester: best for systems 20 gallons and up. Specs, compatibility math, sizing risks, and alternatives before you buy.

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Who it is for

Good fit for

✓ 20+ gallon systems, per the catalog fit range.
✓ Keepers who test this parameter on a schedule and want a numeric reading instead of color-matching.

Not a fit for

✕ Tanks under about 20 gallons; it is sized above them.
✕ A first purchase before the heater, ATO, and maintenance routine are stable.

Listed features

Standalone automated tester for Alk, Ca, Mg, NO3, PO4 and organics
High-precision stepper/DC pumps + colorimetric photosensor
WiFi with iOS/Android app
Talks to Dosetronic, Alkatronic, Solartronic, Powertronic
Reagents sold separately

Specs checked against bulkreefsupply.com.

Compatibility math

Build role

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

Example: Focustronic Mastertronic Automated Water Tester 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.
Focustronic Mastertronic Automated Water Tester best for systems 20 gallons and up; confirm that range against the final display volume, sump volume, and livestock plan.

Alternatives to compare

Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC
Budget-tier alternative in the same category.
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.

Full spec snapshot

Category: Controllers
Build tier: Premium
Estimated price: $910
Tank fit range: best for systems 20 gallons and up
Format: Automated Multi Parameter Tester

Questions

What tank size is the Focustronic Mastertronic Automated Water Tester for?

ReefCrafter's catalog fit range for it is 20+ gallon systems. Confirm that against your final display volume, sump volume, and livestock plan rather than the box label alone.

What should I compare the Focustronic Mastertronic Automated Water Tester against?

Hanna Instruments HI736 Marine Phosphorus Ultra Low Range (ppb) Checker HC (Budget-tier alternative in the same category); 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).