How many parameters does the Hach DR900 measure?

The Hach DR900 measures 48+ parameters using 90+ pre-programmed methods. It operates at four LED wavelengths (420, 520, 560, and 610 nm) with automatic wavelength selection based on the selected method. Parameters include free chlorine, total chlorine, monochloramine, iron, manganese, phosphorus, ammonia, nitrate, nitrite, COD, turbidity, color, pH, dissolved oxygen, hardness, alkalinity, and dozens more.

What is the difference between the Hach DR900 and the DR300?

The DR300 is a single-parameter instrument — each unit is factory-configured for one specific parameter (chlorine, iron, phosphate, bromine, etc.) using one fixed wavelength. The DR900 is a multiparameter instrument that measures 48+ parameters across 4 wavelengths using 90+ pre-programmed methods, all in a single instrument. The DR900 also adds a data log (500 results), USB connectivity for data export and firmware updates, user-programmable methods, Standard Adjust calibration, and Operator/Sample ID tagging. The DR300 is lower cost per parameter but requires a separate instrument for each test.

What sample cells does the Hach DR900 use?

The DR900 accepts three sample cell types through one cell compartment: (1) 16-mm glass test vials (most common Hach reagent kits use these), inserted using the included cell adapter; (2) 1-inch (25 mm) round glass cells, inserted directly into the round cell compartment without the adapter; (3) 1 cm / 10 mL plastic sample cells, also inserted directly. The cell adapter must be in place for 16-mm vials and removed for round cells and 1 cm cells.

How does Standard Adjust work on the DR900?

Standard Adjust modifies the stored factory calibration to align the instrument reading to a known standard. Run a complete test on a verified standard solution near the top of the method range, then go to Options > Advanced Options > Standard Adjust. Enter the known concentration of the standard and press OK. The Standard Adjust icon appears on the display. Important: if using both Reagent Blank correction and Standard Adjust, always perform Reagent Blank correction first, then apply Standard Adjust.

How do I export data from the Hach DR900?

The DR900 exports data via the built-in USB mini port without any software installation. Connect via USB cable — the instrument appears as a USB drive on your PC. From the USB Main Menu on the instrument, select Data Log to export the 500-result log as DR900_DataLog.csv and DR900_EventLog.csv files. Results include measurement value, unit, parameter, program name and number, Operator ID, Sample ID, and date/time stamp.

Product Review & Technical Reference — Hach

Hach DR900 Multiparameter Colorimeter: Complete Review & Reference (2026)

Name: Hach DR900 Multiparameter Colorimeter Review
Item: Hach DR900 Multiparameter Portable Colorimeter
Author: Commercial Water Lab

Source: Hach DR 900 User Manual DOC022.97.80344, Edition 4, April 2022 • DR900 Methods Reference DR900_CMS_block.pdf

Product No. 9385100 • 90+ Methods • 48+ Parameters • 420 / 520 / 560 / 610 nm • IP67 • 500 Results Storage

Hach DR900 Multiparameter Portable Colorimeter showing settings menu with Favorites, All Programs, Data Log, and Setup options

Water treatment operator using Hach DR900 Multiparameter Colorimeter at a wastewater treatment facility

Hach DR900 Multiparameter Portable Colorimeter — Product No. 9385100

90+ methods • 48+ parameters • 4 wavelengths • IP67 waterproof • 500-result data log • USB data export. Reagents sold separately.

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Product No.

9385100

Methods

90+ pre-programmed

Parameters

48+

Wavelengths

420 / 520 / 560 / 610 nm

Light Source

LED (4 wavelengths)

Data Storage

500 results

IP Rating

IP67 Waterproof

Power

4× AA alkaline batteries

Connectivity

USB mini (data export)

User Programs

Up to 10 (favorites + custom)

Languages

9 (incl. EN, ES, FR, ZH, AR)

Manual

DOC022.97.80344 Ed.4 (2022)

DR900 vs DR300 — Which Instrument Do You Need?

The single most important thing to understand about the DR900: it is a fundamentally different class of instrument from the single-parameter DR300 Pocket Colorimeters. The DR300 family (chlorine, iron, phosphate, bromine) is built for one parameter per instrument at one fixed wavelength. The DR900 measures 48+ parameters across four wavelengths from a single device. That difference drives every purchasing decision.

DR300 vs DR900 — DECISION GUIDE

DR300 Pocket Colorimeter

✓ Single parameter per unit
✓ Lower instrument cost
✓ Simpler operation — 2 buttons
✓ Compact — fits in a shirt pocket
✓ IP67 waterproof
✗ No data logging or USB export
✗ One instrument per parameter
✗ No Standard Adjust or user programs

Best for: routine monitoring of a single parameter at one site; low budget; minimal data management needs.

DR900 Multiparameter

✓ 48+ parameters, one instrument
✓ 500-result data log + USB export
✓ Standard Adjust calibration
✓ Operator & Sample ID tagging
✓ User-programmable methods
✓ Favorites in <4 key presses
✓ IP67 + drop-tested
✗ Higher instrument cost

Best for: multi-parameter monitoring; compliance reporting with data records; field operators covering multiple sites or test types.

Feature	DR300 (single-param)	DR900 (multiparameter)
Parameters per instrument	1	48+
Pre-programmed methods	1	90+
Wavelengths	1 (fixed)	4 (420, 520, 560, 610 nm)
Data logging	None	500 results with timestamp
USB connectivity	None	USB mini — CSV export
Operator/Sample ID	None	Yes (10 IDs each)
Standard Adjust	SCA only	Full Standard Adjust
User programs	None	Up to 10 (custom + favorites)
Sample cells	Model-specific	16 mm vial, 25 mm round, 1 cm plastic
IP rating	IP67	IP67 + drop-tested
Batteries	4× AAA	4× AA

Complete Technical Specifications

Specification	Value
Product number	9385100
Light source	LED at 420, 520, 560, and 610 nm
Wavelength selection	Automatic based on selected program
Pre-programmed methods	90+ methods
Parameters covered	48+
User programs / favorites	Up to 10 combined
Data storage	500 results (data log)
Data export	USB mini — DR900_DataLog.csv and DR900_EventLog.csv
Operator IDs	Up to 10
Sample IDs	Up to 10
Display	Backlit LCD
Keypad	6 keys: POWER, HOME, SETTINGS, BACKLIGHT, navigation d-pad, 2 soft keys
Sample cells accepted	16-mm glass test vials (with adapter); 25 mm (1-inch) round glass cells; 1 cm / 10 mL plastic cells
IP rating	IP67 waterproof (submersible to 1 m for 30 min)
Drop resistance	Drop-tested per IEC 68-2-32
Power source	4× AA alkaline batteries
Languages	English, French, Spanish, Portuguese, Chinese (Simplified), Japanese, Korean, Thai, Arabic
Manual	DOC022.97.80344, Edition 4 (April 2022)

Sample Cells — Three Types, One Compartment

The DR900 accommodates all three Hach sample cell formats through a single cell compartment using a removable cell adapter. Using the wrong cell type or omitting/including the adapter incorrectly will produce inaccurate results — the optical path length changes with cell diameter.

Cell Type	Size	Adapter Required	Common Use
16-mm glass test vial	16 mm diameter	Yes — adapter must be installed	Most Hach reagent kit methods; the most common cell type across the 90+ methods
25 mm round glass cell	1-inch (25 mm) diameter	No — insert directly	DR300-compatible methods (chlorine DPD, iron FerroVer, phosphate); large sample volume methods
1 cm / 10 mL plastic cell	1 cm square	No — insert directly	Select methods; avoid scratched or cloudy cells

Cell adapter orientation matters. When using 16-mm vials, install the cell adapter with the correct orientation for the vial to seat in the optical path. Refer to Figure 3 in the user manual for the correct adapter position. Wipe vial exteriors with a lint-free cloth before inserting — fingerprints on the optical surface affect absorbance readings.

Keypad — 6-Key Interface Reference

Key / Control	Function
POWER	Turn instrument on or off. Hold to power off from any screen.
HOME	Return to the main reading screen from any menu.
SETTINGS	Access the Settings menu: Setup (language, date/time), Operator ID, Sample ID, and instrument configuration.
BACKLIGHT	Toggle the display backlight on and off for use in bright outdoor conditions or to extend battery life.
Navigation d-pad (4-way)	UP/DOWN to scroll through program lists, menus, and numeric values. LEFT/RIGHT to navigate between fields. Confirms selections when used as directed by screen prompts.
Soft keys (2×)	Context-sensitive. Label changes based on the active screen. Most common labels: Options, Select, Start, OK, Done, Back.

Selecting and Running a Program — Standard Workflow

Power on the instrument

Press POWER. The main reading screen displays the last used program. Battery level appears in the upper-right corner.

Select a program

Press HOME → Options → All Programs. Scroll alphabetically or numerically to find the method. Highlight and press Start (right soft key). For frequently used tests, add to Favorites first (see below) for access in fewer than 4 key presses.

Assign Operator ID and Sample ID (if required)

Press SETTINGS → Operator ID to select a pre-entered ID. Press SETTINGS → Sample ID to assign a sample location. Both tags appear in the data log entry for this reading.

Prepare the blank cell

Fill the appropriate sample cell with the sample water (no reagent). Wipe the exterior with a lint-free cloth. Install the cell in the instrument (with or without adapter depending on cell type). Press the Zero soft key. The instrument subtracts the sample’s natural absorbance from the subsequent reading.

Prepare the sample cell with reagent

Follow the specific method procedure document for the selected parameter — add the correct reagent type and quantity, observe any mandatory reaction time, and swirl or mix as directed. Wipe exterior clean before inserting.

Insert sample cell — press Read

Insert the reagent-containing sample cell into the compartment. Confirm correct adapter status for the cell type. Close the compartment lid if applicable. Press Read (right soft key). Result displays in the configured unit.

Reading is automatically stored

Every reading is automatically stored to the data log (500-result capacity, FIFO). The entry includes parameter, value, unit, program number, Operator ID, Sample ID, and date/time stamp.

Interpret the “+++” and “---” over-range indicators

“+++” means the measured value exceeds the upper limit of the method range — dilute the sample with reagent-demand-free water and multiply the result by the dilution factor. “---” means the value is below the lower detection limit of the method — verify the test procedure and reagent quality.

Favorites — Access Any Method in Under 4 Key Presses

Add to Favorites immediately after finding a method. The Favorites list is the operational efficiency feature most operators underuse. Once a method is in Favorites, it appears at the top of the program selection screen — no scrolling through 90+ programs. Maximum 10 programs across Favorites and User Programs combined.

Select any program from All Programs

Navigate to HOME → Options → All Programs. Highlight the target method.

Press Options → Add to Favorites

The method is saved to the Favorites list and will appear at the top of the HOME → Options screen on future power-ons.

Reagent Blank Correction — Step by Step

The reagent blank correction removes background absorbance contributed by the reagent itself — essential when reagents have inherent color or when lot-to-lot variation is significant. Without it, residual reagent color adds a systematic positive offset to every reading.

Repeat for every new reagent lot. The reagent blank correction is only valid for the specific lot of reagent used when the blank was entered. When a new lot is opened, always re-run the blank procedure before testing samples.

Select the applicable program

Navigate to and start the method you want to apply the correction to.

Press Options → Advanced Options → Reagent Blank

This opens the reagent blank entry mode.

Prepare a blank using deionized water instead of sample

Run the complete test procedure using deionized water in place of the actual sample — add the same reagent, observe the same reaction time, swirl as directed. Do not shortcut the procedure.

When the reading appears — press OK to store as the blank

The value displayed is the reagent’s contribution to absorbance at zero actual analyte concentration. Pressing OK stores it. The Reagent Blank icon now appears on the measurement screen — confirming the correction is active.

All subsequent readings are automatically corrected

The stored blank value is subtracted from every result for this program until a new blank is entered or the correction is cleared.

Standard Adjust — Step by Step

Standard Adjust modifies the stored factory calibration to align the instrument reading to a verified known standard. Use this when a standard solution at a known concentration gives a reading that differs from the expected value — indicating instrument drift, cell variation, or lot-specific reagent differences.

If using both Reagent Blank and Standard Adjust — Reagent Blank FIRST. Perform the Reagent Blank correction before applying Standard Adjust. Reversing the order produces an incorrect calibration offset.

Run a complete test on a known standard solution

Use a verified standard solution at a concentration near the top of the method range. Follow the complete test procedure including reagent addition and reaction time.

Press Options → Advanced Options → Standard Adjust

The display shows the current reading from Step 1.

Enter the known concentration of the standard — press OK

Use the navigation keys to enter the certified concentration. Press OK or Done to apply. The Standard Adjust icon appears on the display confirming the offset is active.

Standard Adjust vs SCA on the DR300: The DR900’s Standard Adjust is functionally equivalent to the DR300’s SCA (Standard Calibration Adjust) but applies across any method without the DR300’s reagent-specific standard range requirements. Use it any time a verified standard confirms the factory calibration has drifted.

Operator ID & Sample ID — Data Traceability

The Operator ID and Sample ID features are the DR900’s primary tool for regulatory data traceability — especially relevant for compliance monitoring programs where records must be attributable to a specific operator and sample location.

Feature	Capacity	Appears In	Access Path
Operator ID	Up to 10 IDs	Every data log entry; USB export CSV	SETTINGS → Operator ID
Sample ID	Up to 10 IDs	Every data log entry; USB export CSV	SETTINGS → Sample ID

For multi-site or multi-operator programs: set up all Operator IDs and Sample IDs before field deployment. Operators select their ID from the pre-loaded list — no keyboard entry required in the field. The CSV export from the USB data log then includes fully attributed records for every measurement.

USB Functions — Data Export, Firmware, Programs

Connect the DR900 to a PC via the included USB mini cable. No software installation is required — the instrument appears as a standard USB drive. The USB Main Menu on the instrument display presents three options:

USB Function	What It Does	File Name / Notes
Data Log export	Exports all 500 stored results to CSV files on the PC	DR900_DataLog.csv (results) • DR900_EventLog.csv (events)
Firmware update	Updates instrument firmware from a PC-downloaded file	File must be named DR900.bin; select Update DR900 from USB menu
Program management	Import and export user programs between instruments or from PC	Enables standardizing custom methods across a fleet of DR900s

Data export procedure: Select Data Log from the USB Main Menu on the instrument (not just the PC file manager). Use the instrument’s Disconnect USB option before physically unplugging the cable to prevent file corruption. Do not disconnect while a transfer is in progress.

Creating a User Program

User programs allow operators to store custom measurement methods not covered by the 90+ factory programs, or modified versions of existing methods. Maximum 10 programs across user programs and favorites combined.

Navigate to HOME → Options → All Programs → Options → User Programs

This opens the user program creation interface.

Select a wavelength: 420, 520, 560, or 610 nm

Choose the wavelength appropriate for the colorimetric chemistry of your method. Refer to the reagent manufacturer’s documentation for the correct measurement wavelength.

Enter calibration data (absorbance / concentration pairs)

Enter the calibration points that define the concentration curve for your method. More points across the range produce a more accurate calibration.

Name and save the program

Assign a name. The program is saved and appears in the Favorites / User Programs list. It can also be exported via USB and imported onto other DR900 instruments for fleet standardization.

All 48+ Parameters — Complete Method List

The DR900 comes pre-loaded with 90+ methods covering the following 48+ parameters. Wavelength is automatically selected by the instrument based on the method selected. All method numbers and ranges from the official DR900 Methods Reference (DR900_CMS_block.pdf, Hach).

Alkalinity, Total

0–500 mg/L CaCO₃

Method 10239

Ammonia Nitrogen

0.01–0.50 / 0.4–50 mg/L

Methods 8155, 10031

Bromine, Total

0.05–4.50 / 0.2–10.0 mg/L

Method 8016

Chlorine, Free

0.02–2.00 mg/L

Method 8021 (DPD)

Chlorine, Total

0.02–2.00 mg/L

Method 8167 (DPD)

Chlorine Dioxide

0.01–0.50 mg/L

Method 8138

Chromium, Hex

0.005–0.700 mg/L

Method 8023

Chromium, Total

0.01–0.70 mg/L

Method 8024

COD (Cr)

0–1500 mg/L

Methods 8000, 10211

Color, True/Apparent

0–500 PCU

Method 8025

Copper

0.04–5.00 mg/L

Method 8506

Cyanide

0.002–0.240 mg/L

Method 8027

Dissolved Oxygen

0–12 mg/L

Method 8166

Fluoride, SPADNS

0.02–2.00 mg/L

Method 8029

Hardness, Total

0–400 mg/L CaCO₃

Method 8213

Hydrogen Peroxide

0.02–1.00 mg/L

Method 8222

Iron, Total

0.02–3.00 mg/L

Method 8008 (FerroVer)

Iron, Dissolved

0.02–3.00 mg/L

Method 8008

Lead

0.001–0.100 mg/L

Method 8033

Manganese

0.006–0.700 mg/L

Method 8034

Mercury

0.001–0.100 mg/L

Method 8026 (Dithizone)

Molybdenum

0.01–40.0 mg/L

Method 8036

Monochloramine

0.04–4.50 mg/L

Method 10171

Nickel

0.01–0.70 mg/L

Method 8037

Nitrate, LR

0–0.50 mg/L NO₃−-N

Method 8039

Nitrate, HR

0–30.0 mg/L NO₃−-N

Method 8039

Nitrite

0.002–0.300 mg/L NO₂−-N

Method 8507

Ozone

0.01–1.00 mg/L

Method 8311 (Indigo)

pH, Colorimetric

6.5–8.5

Method 8025

Phosphate, Reactive

0.02–2.50 mg/L PO₄³−

Method 8048 (PhosVer 3)

Phosphorus, Total

0.06–3.50 mg/L PO₄³−

Method 8190

Potassium

0–8.00 mg/L

Method 8049

Residual Chlorine

0–10.0 mg/L

Method 10069 (HR)

Silica, LR

0.01–1.00 mg/L SiO₂

Method 8185

Silica, HR

1–100 mg/L SiO₂

Method 8186

Sulfate

0–70 mg/L

Method 8051

Sulfide

0.01–0.70 mg/L

Method 8131

Surfactants (Anionic)

0.05–0.500 mg/L

Method 8028

Thiocyanate

0.005–2.00 mg/L

Method 8000

Turbidity

0–1000 NTU

Method 8195

Zinc

0.01–3.00 mg/L

Method 8009

Full method list from DR900_CMS_block.pdf (Hach Methods Reference). Ranges and method numbers subject to change with firmware updates. Download the current methods reference from hach.com for the most current data.

Maintenance

Cleaning the Instrument Exterior

Clean the exterior with a moist cloth and mild soap solution, then wipe dry. The IP67 enclosure permits rinsing under running water. Do not use abrasive cleaners, solvents, or high-pressure water jets.

Cleaning Sample Cells

Rinse immediately after each use

Rinse cells with deionized water immediately after each test — do not allow reagents to dry in the cell. Dried reagent residue is the leading cause of background absorbance errors.

Mild soap and water for general cleaning

Use a mild laboratory detergent with warm water. Rinse thoroughly with deionized water. Dry with a lint-free cloth or air dry.

Method-specific cleaning requirements override general guidance

Certain methods require specific cleaning procedures (e.g., nitric acid rinse for trace metal methods; solvent rinse for organic methods). Always check the specific method procedure document first. Method-specific requirements take precedence.

Replace scratched or etched cells

Any visible scratch or etching in the optical path permanently affects readings. Replace cells that have been scratched by abrasive cleaners or physical damage.

Battery Replacement

Always replace all 4 AA batteries simultaneously. Do not mix new and used batteries or batteries from different brands. Do not use rechargeable batteries — the DR900 requires AA alkaline only. Replace when the battery icon indicates low power. Screw the battery compartment cover to 1–1.4 N·m torque when closing.

Troubleshooting

Symptom	Likely Cause	Resolution
“+++” over-range display	Sample concentration exceeds the upper limit of the selected method range	Dilute sample with reagent-demand-free water; retest; multiply result by dilution factor
“---” under-range display	Value below method’s lower detection limit; reagent not added; procedure error	Verify reagent was added; confirm procedure; check reagent expiry date; repeat test
High background reading (blank)	Contaminated sample cell; reagent carryover from previous test	Clean or replace sample cell; triple-rinse with deionized water; run Reagent Blank correction
Inconsistent results between replicate tests	Reaction time not observed; swirling incomplete; cell not wiped; reagent lot variation	Strictly follow method procedure timing; run Reagent Blank for new lot; verify standard with Standard Adjust
Standard Adjust reading outside expected range	Standard concentration incorrect; standard expired; reagent lot change	Prepare a fresh standard from a verified source; re-run Reagent Blank before Standard Adjust
Display will not power on	Dead or incorrectly installed batteries	Verify correct battery orientation; replace all 4 AA batteries simultaneously; check battery compartment screw
Adapter not seating correctly	Cell adapter installed in wrong orientation or damaged	Remove adapter, check orientation against Figure 3 in user manual, reseat
USB not recognized by PC	Cable not fully seated; instrument not powered on; firmware issue	Reconnect cable with instrument powered on; try a different USB port; check for firmware update

Replacement Parts & Accessories

Item	Notes
Sample cell, 16 mm glass test vial	Most common — used with the cell adapter. Verify current item number at hach.com for your specific method.
Sample cell, 25 mm round glass	Compatible with DPD chlorine, FerroVer iron, and other standard methods that use the 25 mm cell format.
Sample cell, 1 cm plastic (10 mL)	Select methods only. Replace when scratched or cloudy.
Cell adapter	Required for 16-mm vials. Contact Hach if original is lost or damaged.
USB mini cable	Standard USB mini-B. Any replacement USB mini-B cable is compatible.
Batteries, AA alkaline (4-pack)	Standard AA alkaline. Do not use rechargeable.
Instrument case / protective cover	Contact Hach distributor or hach.com for current item numbers and regional availability.

Hach DR900 Multiparameter Portable Colorimeter — 9385100

90+ methods • 48+ parameters • IP67 • 500-result data log • USB export. Complete instrument without reagents.

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Related DR300 Single-Parameter References

If you need a dedicated single-parameter instrument for one specific test, the DR300 family covers the most common parameters: