Automatic pool filling: everything you need to know
Tired of watching your pool level, topping up by hand with a hose, or coming back from holiday to find your pump has run dry? Automatic pool filling is the answer — simple, reliable and suitable for all types of pool.
In this guide we explain how it works, what options are available and how to choose the right system for your situation.
Why automate pool filling?
A pool loses water all the time. In summer, evaporation alone (sun, wind) can account for up to 3 cm of water a week, or several hundred litres. Add splashing, repeated swimming and, depending on your installation, slight technical losses.
Consequences of a level that is too low:
- The pump loses its prime — it sucks in air instead of water and can burn out within minutes (allow €500 to €1,000 for repairs)
- The skimmer loses efficiency — it draws in air rather than surface debris
- The automatic cover is weakened — an insufficient level accelerates wear
- Filtration deteriorates — unstable level = less effective chemical treatment = higher consumption of products
An automatic filling system solves all these problems at once, without supervision, 24/7.
How does an automatic filling system work?
The basic principle is simple: a sensor detects the drop in water level and opens the water supply automatically. When the level reaches the desired threshold, the supply closes. Depending on the model, the hysteresis — that is, the difference between the high and low levels — can vary.
There are two main families of sensors:
- The mechanical sensor — the same principle as a toilet cistern. No electricity, no batteries, reliable and durable. This is the system used by NivOmatic.
- The electronic probe — detects the level by conductivity or pressure. It needs a power supply and regular maintenance.
In both cases, the system is connected to your domestic water supply (or borehole) via a supply pipe — or even a simple garden hose in the case of NivOmatic.
The different types of system
1. The sealed-in mechanical float regulator
This is the most common solution for private owners. The device has to be ordered when the pool is ordered. The regulator is set into the pool surround and connected to a polyethylene pipe that must be laid during construction (water supply).
Advantages: permanent installation. Compatible with all pools. Affordable price (€60, plus installation of the water supply and fitting of the regulator by a professional — allow €300–350).
Drawback: The system must be put in place when the pool is built. Once sealed in, when it ages it is often no longer possible to find spare parts and it becomes useless, or even a source of leaks.
2. The built-in mechanical regulator
The same principle, installed permanently but removable — in the skimmer, under the automatic cover, or through a wall passage. As discreet as a sealed-in regulator, it has the advantage that it can be removed and serviced at any time. NivOmatic meets all these criteria and, in some circumstances, can even take over from a sealed-in regulator that no longer works. NivOmatic can also be installed in most filter blocks (level regulation is generally not provided for in this type of pool).
Advantages: invisible or very discreet, it can be added to a pool even after construction. Lifetime maintenance.
Drawback: installation is usually affordable but may sometimes require a pool professional on some sites.
3. The electronic system
Made up of a level probe combined with a solenoid valve. High precision, configurable. Used mainly on infinity pools with tanks or balance tanks, or in professional installations.
Advantages: precision, configuration with several probes, compatible with balance tanks.
Drawback: high price (€300–800), professional installation required, power consumption, reliability, maintenance.
4. The removable level regulator
This is one of NivOmatic’s favourite uses. It is used for regular topping-up to the right level without forgetting (I put the device in place, open the tap and walk away…), and for automatic filling while you are away (I set the device in place and turn on the water; it regulates the level until I return).
Advantages: precision, ease of use, no professional needed, lifetime maintenance, price (€129)
Drawback: The device has to be placed on the coping each time you top up, unless you choose to install it permanently.
The Removable NivOmatic is put in place and removed as needed; the NivOmatic fixed or removable is the same unit, but supplied with several accessories that also allow a fixed installation.
How to choose the right system
The answer depends on your situation:
| Your situation | Recommended solution |
|---|---|
| In-ground or above-ground pool, private use | Removable mechanical regulator (NivOmatic) |
| You want it to stay permanently discreet | Fixed mechanical regulator (NivOmatic “fixed or removable”) |
| Infinity pool / balance tank | Suspended NivOmatic or electronic regulator |
| Professional installation / hotel | CCEI electronic system or similar |
For the vast majority of residential pool owners, a removable mechanical regulator is the ideal solution: simple, reliable, maintenance-free and economical.
Installation: what it involves in practice
With a removable mechanical regulator such as NivOmatic, installation takes 3 steps:
- Place the stainless steel angle bracket on your coping (flat, sloping or rounded — the bracket can be adapted to any shape)
- Connect the supply hose (supplied, 2 m) to your tap or garden hose — standard 3/4″ connection
- Set the desired water height on first use (from 5 to 26 cm below the coping)
That is all. No tools, no technical skills, no changes to your installation. Actual time: about 2 minutes.
For a fixed (permanent) installation, additional accessories allow the regulator to be integrated into your skimmer or under your automatic cover.
The real savings
A level regulator is not an expense — it is an investment that pays for itself in less than a season:
- €30 to €50 saved on water — automatic filling compensates for evaporation without overfilling or overflowing
- €50 to €80 saved on chemicals — a constant level ensures the skimmer works perfectly and filtration is optimal, so consumption is lower
- Up to €800 avoided — the cost of a pump burnt out through lack of water. The cost of a damaged automatic cover is even higher!
- 0 watts consumed — the mechanical system works without electricity, using water pressure
Over a 10-year lifespan, the economic case is clear.
Frequently asked questions
Does automatic filling work with an above-ground pool?
Yes. A mechanical regulator such as NivOmatic is compatible with all types of pool: in-ground, tubular above-ground, self-supporting, wood or steel. The angle bracket adapts to any edge.
Can it be used with borehole water or harvested rainwater?
Yes, provided the pressure is at least 1 bar. The system works with mains water, a borehole, a booster pump or a rainwater harvesting system. It is supplied with a strainer washer.
Does the system protect against overflowing when it rains?
No — the level regulator only handles filling (it opens the water supply when the level drops). The overflow must have been installed by your pool builder during construction. The two systems are complementary.
Do I need a plumber to install it?
No. A removable regulator connects to a simple garden hose. No technical skills required.
How long does a mechanical regulator last?
A quality mechanical regulator such as NivOmatic (316L stainless steel, NF-certified valve, UV-resistant ABS plastic, EPDM membrane, reinforced UV-treated hose) lasts 10 to 15 years. The only wearing part is the membrane, which can be replaced in 10 minutes for about €10.
The NivOmatic solution
NivOmatic has been making pool level regulators for over 15 years in its workshop in the Périgord. A patented, certified product with maintenance guaranteed. More than 6,000 owners use it in France.
Compatible with all pools. Installed in 2 minutes. No electricity. 2-year warranty.
