Aquael Ultra Heater Day&Night unbreakable heater, 25 to 200 W
Regular price
¥5,100
Regular price
Sale price
¥5,100
Unit price
/
per
¥1,700 × 3 with no fees
Klarna.
The Aquael Ultra Heater Day&Night is a submersible aquarium heater with a shatterproof plastic body, adjustable from 20 to 33 °C. Its light sensor lowers the temperature at night and restores it in the morning. Six power ratings, from 25 to 200 W, for a tank of 10 to 200 litres.
Customer support 7 days a week by email
Delivery within 2 to 15 business days
100 % secure payment
The summary
- What it is: a submersible heater with a shatterproof plastic body, from 25 to 200 W.
- Which wattage: from 10 to 25 L for the 25 W, up to 200 L for the 200 W.
- Day and night mode: a light sensor lowers the set temperature in the evening.
- Its accuracy: an electronic thermostat adjustable from 20 to 33 °C, accurate to 0.25 °C.
A flat, unbreakable aquarium heater that lowers the temperature at night
The Aquael Ultra Heater Day&Night is an aquarium heater that is submerged in the tank, like a standard heater, but its body is made of unbreakable plastic instead of glass. Its electronic thermostat holds the chosen setting between 20 and 33 °C, to within 0.25 °C. Its distinctive feature is a light sensor: at nightfall it gently lowers the water temperature, then returns it to the daytime value in the morning, as in a natural environment. It comes in six power ratings, from 25 to 200 W, for your aquarium of 10 to 200 litres.
🌗 Day and night mode
A small switch, under the sensor cover, selects between two modes. In constant mode, the water stays at the same temperature day and night. In day and night mode, you set a day temperature and a night temperature, usually 1 to 2 °C lower. When the light in the room fades in the evening, the sensor switches the heater to night mode and the water gradually cools to the night value. At daybreak, the heater gradually starts up again, until the day temperature is reached. Your fish thus enjoy the natural difference between day and night, with no sudden change.
A thermometer to monitor the overnight drop
A suction-cup aquarium thermometer, stuck on the opposite side from the heater, shows you the real effect of night mode throughout the tank. Read it in the evening, then in the morning before the lights come on: you will know whether the programmed drop has been reached and whether it suits your fish. Placed far from the heater, it measures water that has already circulated around the tank, not the water leaving the unit.
🛡️ A flat, unbreakable body
The unbreakable plastic casing does not get hot to the touch, which makes this a safe heater if you keep aquatic turtles or large fish that knock the decor about. Its flat shape sits snugly against the glass, and its double-sided bracket, fitted with two suction cups, attaches it to the back, front or side pane. Three indicator light colours show the temperature range set: blue from 20 to 23 °C, green from 24 to 29 °C, red from 30 to 33 °C. Its electronics regulate the heating power to avoid sudden surges and limit energy consumption. The height ranges from 16.3 cm for the 25 and 50 W models to 27.4 cm for the 150 and 200 W models.
🌱 In aquaponics
In a small indoor aquaponics system, warm water stimulates the fish's appetite and the activity of the bacteria that convert their waste into nitrates for the plants, one stage of the nitrogen cycle in aquaponics. The day and night mode reproduces the slight drop in temperature at night that fish experience in the wild; a difference of 1 to 2 °C is enough. For a fish tank of 100 to 200 litres, the 150 W or 200 W model is suitable; place it near the water return. The guide to choosing fish for aquaponics gives the right temperature for each species.
🚦 Reading the indicator lights
The colour of the indicator light tells you which range the set temperature falls in, and its behaviour tells you where the water stands. While the water is colder than the set temperature, the light pulses, showing that the unit is heating; when the set temperature is reached, it stays on steadily; if it flashes rapidly, your water is warmer than the set value, which happens in summer in a warm room. In day and night mode, a white light indicates that the unit is in its day phase. The set temperature is adjusted in steps of 1 °C, and a built-in thermal safety cuts the heating in the event of overheating.
⚖️ Choosing the power
The volume ranges of the six models overlap: a 40-litre tank falls within the range of the 50 W as well as that of the 75 W. In a heated room, the power whose range covers your volume is enough, because the water loses little heat. If your aquarium is in a cool room, a conservatory or a basement, choose the model above instead, which will reach the set temperature faster and hold it without running continuously.
Technical specifications
The essentials
- Power ratings
- 25, 50, 75, 100, 150 or 200 W
- Tank volume
- 10 to 200 L depending on the power
- Adjustment
- 20 to 33 °CIn steps of 1 °C.
- Precision
- 0.25 °C
Functions
- Modes
- Constant, or day and nightChosen using the switch under the sensor cover
- Sensor
- Room lighting
- Indicator lights
- Blue, green or red depending on the set temperature
- Housing
- Unbreakable plastic, flat
Height and mounting
- 25 and 50 W
- 16.3 cm
- 75 and 100 W
- 20.8 cm
- 150 and 200 W
- 27.4 cm
- Fixing
- Double-sided holder, 2 suction cups
Volume by power
- 25 W
- 10 to 25 L
- 50 W
- 15 to 50 L
- 75 W
- 35 to 75 L
- 100 W
- 60 to 100 L
- 150 W
- 90 to 150 L
- 200 W
- 130 to 200 L
10 further specifications are available in the detailed view.
In the box
- 1 Aquael Ultra Heater Day&Night heater in the wattage of your choice
- 1 double-sided holder with 2 suckers
Power ratings, volumes, heights, adjustment range, accuracy and functions taken on 11/10/2026 from the information sheet and the product page for the Aquael Ultra Heater Day&Night.
What power for your aquarium?
Six power ratings. The tank volume decides.
Which power rating?
Answer one question, and the table highlights the power that suits you.
| 25 WYour choice | 50 WYour choice | 75 WYour choice | Recommended 100 WYour choice | 150 WYour choice | 200 WYour choice | |
|---|---|---|---|---|---|---|
| Sizing | ||||||
| Maximum volume (L) | 25 L | 50 L | 75 L | 100 L | 150 L | 200 L |
| For | A tank of up to 25 L | A tank of 25 to 50 L | A tank of 50 to 75 L | A tank of 75 to 100 L | A tank of 100 to 150 L | A tank of 150 to 200 L |
| Height | 16.3 cm | 16.3 cm | 20.8 cm | 20.8 cm | 27.4 cm | 27.4 cm |
| Price | ¥5,100 | ¥5,500 | ¥5,800 | ¥6,400 | ¥6,700 | ¥7,100 |
25 W
Sizing
Maximum volume (L)25 L
ForA tank of up to 25 L
Height16.3 cm
50 W
Sizing
Maximum volume (L)50 L
ForA tank of 25 to 50 L
Height16.3 cm
75 W
Sizing
Maximum volume (L)75 L
ForA tank of 50 to 75 L
Height20.8 cm
100 WRecommended
Sizing
Maximum volume (L)100 L
ForA tank of 75 to 100 L
Height20.8 cm
150 W
Sizing
Maximum volume (L)150 L
ForA tank of 100 to 150 L
Height27.4 cm
200 W
Sizing
Maximum volume (L)200 L
ForA tank of 150 to 200 L
Height27.4 cm
Volumes recorded on 11/10/2026 from the Aquael information sheet.
Help choosing
A question about your aquarium
Estimate your
delivery time
Your estimate
Delivery
Estimated time
It covers preparing your order and then the transit time quoted by the carrier, counted in working days.
It is not a guaranteed delivery date: public holidays, peak periods, customs or a carrier delay can extend it. The exact amount, in your currency, is worked out in the cart once your address is entered.
Delivered to your home by Colissimo or Chronopost, as you prefer at checkout. The exact cost is shown in the basket, according to the total weight of your order.
Frequently asked questions
8 questions
6 key questions, 8 in the detailed view
You may also like
Related articles
Fish
Which fish to choose for aquaponics?
The species you choose sets the temperature the heater has to hold.
Read the article
Fish
Raising tilapia in aquaponics
A warm-water species that needs a stable temperature all year round.
Read the article
Understanding
Start-up
Getting started with an aquaponic system
The first few weeks, when temperature matters most.
Read the article
Winter
Let us talk about your project
A question about this product or your setup? Our team will answer and advise you.
Interest-free instalment payments
Offered depending on the cart amount, at checkout.
Delivery in 2 to 15 working days
Depending on the products and shipping sites. Estimate by destination in the estimator on this page.
After-sales service 7 days a week by email or chat
Our team answers all your questions.
Shop responsibly
Become part of the change.
