Skip to main content
ToolboxReal Time MonitoringDissolved Oxygen Sensor
A weather sensor enclosure mounted on a dock post above a calm lake, with forested shoreline in the background
Real Time Monitoring

Dissolved Oxygen Sensor

Oxygen is what kills fish, and it does it at five in the morning when nobody is watching.

What it answers

Is my lake losing oxygen — and when does it happen?

$1,250

Checkout arrives with the store connection. Orders attach to the lake on your account.

Product category
  • Physical ProductShips to you
  • ConsumableLab testing
  • ServiceBy the Lake Pulse Boathouse
  • CombinationKit with multiple items
  • In stock

    Ships in 3–5 business days

  • Shipping

    Flat-rate to your front door. Shipping details

  • If something's wrong

    Damaged, missing, or a result that looks off — tell us and we make it right.

Overview

Turnaround

Streams to your Portal continuously once deployed.

When to use it

What problem does this solve for our lake?

  • A summer fish kill is almost never a mystery to a limnologist and almost always a mystery to the lake association that woke up to it. The mechanism is well understood: algae and plants produce oxygen through the day and consume it all night, and in a productive lake the pre-dawn minimum can fall below what fish can survive. By the time anyone is on the water, photosynthesis has restarted and the oxygen has recovered. The evidence is gone before breakfast.
  • A spot measurement taken during a site visit is therefore close to useless for this question. It samples the wrong hour. Continuous logging is the only way to capture the daily minimum, and the daily minimum is the number that determines whether your lake is habitable.
  • The second use is stratification. Through the summer, a deep lake separates into a warm surface layer and a cold bottom layer that no longer exchange. Oxygen in that bottom layer is consumed and not replaced, and when it reaches zero the sediment begins releasing phosphorus back into the water — internal loading, the reason so many lakes fail to improve after their watershed is cleaned up. Deployed on a multi-depth string, this sensor documents that process as it happens rather than inferring it afterward.

What's included?

  • Continuous optical dissolved oxygen sensor with integrated temperature
  • Logging at fifteen-minute intervals through the season
  • Threshold alerting, configured to a level you set
  • Single-depth deployment hardware; multi-depth string configuration available
  • Automatic data upload to the Lake Pulse Portal
  • Online dashboard viewable from phone or any device
  • Optical sensing membrane, which requires no electrolyte and no field calibration between seasons
  • Data flows up to the Lake Pulse cloud and back down into your lake's account, where it can be charted in the Analytics Hub, used to trigger alerts, and shared with your board and members

What's not included

  • Installation. Anchoring, mooring, or dock mounting is yours.
  • A dock, buoy, or fixed deployment point
  • The multi-depth string itself, which is quoted separately based on your lake's depth and thermocline
  • Water quality of any kind beyond oxygen and temperature
  • Nutrients, chlorophyll, or cyanobacteria. Oxygen tells you the consequence, not the cause.
  • Winter operation. Season use, removed before ice-in.
  • Aeration, circulation, or any intervention. This measures; it does not treat.
  • Treatment, remediation, or applicator services

Requirements

  • A deployment point at a location representative of the lake, ideally over the deep hole rather than in a shallow bay
  • Wi-Fi or base station coverage at the deployment site
  • The same position and depth each season, so year-over-year readings compare
  • Seasonal membrane inspection and cleaning; biofouling is the main cause of drift
  • Removal before ice-in
  • A Plus, Lake Admin, or PRO subscription. Syncing a real-time device to a Lake Pulse account requires one of these tiers.
  • Contact the Lake Pulse Boathouse if you have questions.
What you get back

Results

  • Continuous dissolved oxygen in mg/L with percent saturation, viewable from anywhere
  • The daily minimum, which a spot sample will never capture
  • Temperature at the same depth, so oxygen can be read against saturation rather than in isolation
  • Threshold alerts when readings cross a level you set, before a kill rather than after
  • On a multi-depth string, the seasonal development and breakdown of stratification and the onset of hypolimnetic anoxia
  • Data flows up to the Lake Pulse cloud and back down into your lake's account, where it can be charted in the Analytics Hub, used to trigger alerts, and shared with your board and members
  • Results are found in your lake's portal, accessible only to Plus, Lake Admin, and PRO subscription tiers

Pro tips

  • Set the alert at 5 mg/L, not at zero. Most warm-water fish are under stress well before the water is lethal, and the point of an alert is lead time.
  • Deploy over the deep hole. A sensor in a shallow bay measures the bay. The oxygen question that matters is what is happening at depth.
  • A single depth answers half the question. If internal loading is your concern, you need the bottom layer, and that means a string.
  • Watch the daily swing, not just the value. A lake oscillating six mg/L between afternoon and dawn is telling you it is heavily productive, regardless of where the average sits.
  • Biofouling is the failure mode. A membrane left uncleaned through a productive August will read low, and low readings are the ones you are least likely to question.
  • Pair it with chlorophyll-a and total phosphorus. Oxygen is the symptom. Those two are the explanation, and a board approving a budget will want both.
  • Take it in before ice. It is the most common way an expensive sensor becomes an expensive lesson.

Lake Pulse sells measurement and monitoring — not treatment or remediation. What you buy here positions you to solve the problem, and to prove whether it worked.

Results sync to your Portal with Plus, Lake Admin & PRO

Results from this product land on your lake's timeline in the Portal — next to everything else your lake has ever measured, instead of in an inbox.

Compare subscriptions

Questions on this?

Our team can help you choose the right solution for your lake, explain how results sync to your Portal, or point you to the right subscription.

Same aisle

More in Real Time Monitoring.

See all

Water Table Watch

Your well and your lake are the same water. Only one of them tells you early.

Answers: Are my lake and its groundwater in balance?

Results sync to your Portal with Plus, Lake Admin & PRO

In stockShips in 3–5 business days

$1,500

View

LakeTemp Sensor

Temperature is the lake's master variable. This is the cheapest way to stop guessing at it.

Answers: How warm is my lake, and how is that changing through the season?

Results sync to your Portal with Plus, Lake Admin & PRO

In stockShips in 3–5 business days

$150

View

LakeLevel Sensor

Ninety-six readings a day, to a fifth of an inch, from a sensor nobody has to visit.

Answers: Is my lake rising or falling, and how fast?

Results sync to your Portal with Plus, Lake Admin & PRO

In stockShips in 3–5 business days

$1,500

View
A woman paddling a kayak alone across a misty morning lake

Lake Pulse

Every lake deserves a timeline. Yours can start this morning.

Get started