Knocking on the silo or a feed-level sensor — what really prevents running out of feed
How much feed is left in the silo? Some farmers knock on the metal and judge by sound, look at the cone through the hatch and count it in their head from experience. Others glance at a phone screen, because the silo weighs itself or has a level sensor. Both ways work, but they differ in accuracy, risk and labour. We compare them one by one — criterion by criterion — so you know when the eye is enough and when it pays to add electronics.
verifiedFrom the team that has organised work on poultry farms for years.
Two methods, one goal: never run out of feed
Feed is the biggest cost on a poultry farm and, at the same time, the one thing that must never run out — a hungry flock means lost weight gain and real losses. So every farmer checks the silo stock somehow. The only question is how: manually by eye, or automatically with a sensor. This is not a “better versus worse” argument but a choice of tool for the scale and situation. For the whole topic, start with the guide on feed silo monitoring.
Eyeballing it: knocking, looking, knowing
The manual method is a set of tricks a farmer masters over time. Knocking on the silo wall — the sound tells you where the feed ends and the empty metal begins. A visual check through the top hatch or a sight glass. Counting in your head: I know how much I poured in, how much the flock eats a day and which day of the cycle it is. It costs nothing and needs no equipment, but it rests on a person — their time, memory and presence on the farm.
A level sensor or load cells
The automatic method measures the stock for you. A level sensor (radar, ultrasonic or cable) tells you how high the feed reaches in the silo. Load cells (pressure sensors under the silo legs) weigh the whole content — the most accurate reading, because it knows the real kilograms, not just the cone height. The reading goes to a phone app. We cover the technology choice itself in wired vs LoRaWAN sensors, and the difference between a ready system and bare sensors in a system versus bare sensors.
Why this choice matters
Three things are at stake: the risk of suddenly running out of feed (the worst scenario on a farm), delivery planning (ordering too early means frozen cash, too late means an empty silo) and the labour time of staff. The more silos and the farther the farm, the more often manual checking fails — not because it is bad, but because you cannot keep up. In the next sections we break both methods down across six hard criteria, then suggest what to choose in your situation.
Knocking on the silo versus a sensor — six criteria
No method is perfect for everything. We compare both one by one: where the farmer’s eye wins and where electronics do. Each point names both sides, so you can judge what pays off for you.
Measurement accuracy: estimate versus kilograms
Knocking and visual checks give a rough idea — “about half left”, “enough for a few days”. An experienced farmer’s judgement can be surprisingly good, but it is still an estimate with an error, especially when feed bridges on the walls. A level sensor gives the height, and load cells give real kilograms with high accuracy. If you want to know the exact stock rather than guess, measurement wins — details in feed silo monitoring.
Risk of suddenly running out of feed
With the manual method the risk is real: someone forgets to check, misreads the sound, the feed bridges and the silo “shows” more than there really is. Running out of feed means a hungry flock and losses in a single day. A sensor with a low-level alarm warns you in advance, whether or not anyone looked at the farm today. This is the main reason farmers at a larger scale reach for automation — not for convenience, but for the safety of the flock.
Time and labour of staff
Checking one silo by eye takes a minute. But with several silos, several times a day, every day for the whole cycle — it adds up, and you have to be on site. A sensor measures without you, around the clock, and you have the reading on your phone from anywhere. The more facilities and the more spread-out the farm, the bigger the time saving. With one silo under the window the difference is small.
Planning deliveries and orders
Manually you order feed “by feel” — and you either order too early (full silo, frozen cash, risk the delivery will not fit) or too late (panic and a rush delivery). A sensor shows the consumption trend, so you see how many days the stock will last and order calmly, in advance. This turns deliveries from firefighting into a planned schedule — easier to agree a date with the supplier and avoid downtime.
Cost: zero versus investing in a sensor
Here eyeballing wins outright — it costs nothing. A level sensor or a set of load cells is a spend on hardware and installation, sometimes per silo. You have to weigh the return: what one episode of running out of feed costs, or cash needlessly frozen in too-early deliveries, against the price of the sensor. With one small silo the investment rarely adds up; with several large ones it usually does. We cover a ready solution versus building it yourself in a system versus bare sensors.
Historical data and consumption
The farmer’s eye leaves no trace — you know “roughly”, but you have no consumption chart for the whole cycle or a comparison between flocks. A sensor records the history: how much feed went down each day, how the flock’s appetite changed, where there was a jump or a drop. This is data for settling the cycle and an early signal of a health problem (a sudden drop in feed intake). You link it with the digital Flock Card and full production records.
Knocking or a sensor — the decision for your farm
The answer depends on scale, distance and how much a mistake costs you. Here are six situations to help you decide when the eye is enough and when it pays to add electronics.
One silo versus many silos
With one silo right by the house, eyeballing can be perfectly enough — you look on the way past, knock, you know. The more silos, the harder it is to keep track of all of them by hand and the easier it is to miss something. With several tanks one screen showing each one’s level turns the round into a single glance. Scale is the simplest decision criterion: one silo — the eye usually suffices; many — automation holds up.
A remote or remotely supervised farm
If you live on the farm and are by the silos every day, manual checking is natural. If the farm is remote, supervised by a worker, or you run several locations, “by eye” means “someone has to be there and remember”. A sensor with a phone reading gives you the feed level without driving over — you check all the facilities from one place. This is often the main argument for electronics, more important than accuracy itself.
Automatic ordering and alarms
A sensor is more than a number on a screen. A low-level alarm takes the duty of remembering off you, and the consumption trend lets you order feed in advance or even set a threshold that triggers an order reminder. Manually, all of this is on you. If constantly watching the stock wears you out, or it is delegated across several people, automation tidies the process and cuts human error.
Cost versus the risk of losses
Reduce the decision to numbers: what one episode of running out of feed really costs (a hungry flock, lower weight gain, a worse cycle result) and how often it happens or could happen to you. If the risk is low and cheap in its effects — the eye is enough. If a single mistake can wipe out the cycle’s profit, a sensor pays off fast. It is not a matter of fashion but a simple risk calculation for your scale and feed cost.
Common mistakes of both methods
Manually: feed bridges on the walls and “by eye” shows more than there is; several people check and each judges differently; in a rush someone skips the round. Automatically: a poorly matched sensor (e.g. for bridging, light feed), uncalibrated weights, treating one wrong reading as gospel without common sense. The combination works best — the sensor measures, while the farmer still understands what the screen shows and knows when to look inside the silo.
Recommendation: monitoring in the app
For a small, single-silo farm watched day to day, eyeballing is fine — do not let anyone tell you that you must buy hardware. But when you have several silos, a remote farm or the price of one run-out is high, level monitoring brings stock, alarms and consumption history into one place. In DlaFerm.pl you see the silo status, link it with the digital Flock Card, and DlaFerm.pl can file your flock records in IRZplus for you — automatically, if you want. You can create a farm account for free and judge for yourself whether automation pays off.
Frequently asked questions about checking feed stock in a silo
Is knocking on the silo a reliable method?add
For an experienced farmer with one silo it can be surprisingly accurate — the sound tells you how high the feed reaches. The catch is that it is still an estimate: feed can hang on the walls (bridge) and mislead the sound, and the method needs someone on site who remembers to check. With one tank under the window it usually suffices; with several silos or a remote farm the risk of error grows.
Level sensor or load cells — which is more accurate?add
Load cells are the most accurate, because pressure sensors under the silo legs weigh the real content in kilograms, regardless of cone shape or feed bridging. A level sensor (radar, ultrasonic, cable) gives a height that has to be converted to mass, so with bridged feed it can be less faithful. Weighing usually costs more and needs installation under the silo, but gives the reading easiest to rely on.
Does a feed sensor pay off with just one silo?add
Often not. With one small silo right by the house that you watch every day, eyeballing usually suffices and the hardware investment rarely adds up. A sensor starts to pay off when you have several silos, a remote or remotely supervised farm, or when a single episode of running out of feed can wipe out the cycle’s profit. It is a simple calculation: the cost of the sensor versus the cost of a mistake times its probability.
How does a sensor help plan feed deliveries?add
A sensor shows not only the current level but the consumption trend, so you see how many days the stock will still last. That lets you order in advance and avoid two extremes: a delivery too early (full silo, frozen cash) and too late (panic and a rush delivery). Instead of reacting to an empty silo, you arrange deliveries into a planned schedule that is easier to agree with the supplier.
Is sensor data useful beyond stock control?add
Yes. The feed consumption history is a valuable health signal — a sudden drop in intake is often the first symptom of a flock problem, before you see anything else. The data also serves to settle the cycle and to compare flocks. It gives the most when you link it with production records, for example the digital Flock Card, where feed intake sits next to weight gain and flock events.
Does electronics fully replace the farmer’s eye?add
No, and that is not the goal. The combination works best: the sensor measures stock accurately around the clock, while the farmer still understands what the screen shows and knows when to look inside the silo — for example when a reading looks suspicious or the feed starts to bridge. Automation removes the routine and the risk of forgetting, but the farmer’s experience and common sense stay irreplaceable.
Keep your feed stock under control with DlaFerm.pl
Want to know the level in every silo without knocking or driving over, get an alarm at low stock and see the consumption trend? We will show you how DlaFerm.pl ties silo monitoring to the Flock Card and IRZplus records. Create a free farm account.
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