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An aquarium water heater is necessary to maintain a comfortable temperature for fish and plants. In practice, it has long been proven that the health and lifespan of the inhabitants of your home ecosystem largely depend on a stable and comfortable water temperature.

The principle of operation of most heaters is approximately the same: in a sealed environment, the heating element gives off heat using electrical energy. Some aquarists prefer to make such heaters themselves, but it should be noted that this is very dangerous: an improperly designed device can not only electrocute fish, but also harm human health. Therefore, we strongly recommend not to experiment, but to buy a water heater for your aquarium.

You can often hear the opinion that it is necessary to choose the heater power at the rate of 1 Watt per liter, but, as a rule, they usually choose equipment with a power of 0.7–0.8 Watts per liter.

Types of water heaters for aquariums

The most commonly used aquarium heaters are:

• Flow-through. Its body is usually made of plastic and is attached to the return hose. external filter vertically. In this case, warm, oxygenated, water. Flow heater significantly saves useful space in the aquarium.
• Submersible. Such a heater aquarium water consists of glass, plastic or titanium. Its body has an elongated cylindrical or flask-shaped shape, and physical properties, providing heat resistance and impact resistance. This device is lowered directly into the water.
• Thermal cables. Usually laid under the ground, they evenly heat all layers of water in the aquarium and provide additional circulation.
• Mats for heating water. Quite a rare type aquarium heaters water, which is installed under the aquarium, and heats it through the bottom.

To maintain the normal functioning of your pet fish, you need to install a water heater. Its presence is mandatory. It does not depend on the room temperature. In this article we will try to answer the questions: how to choose the right water heater for an aquarium and how to install it.

What is a fish water heater?

An aquarium water heater is a special device for heating water. It helps provide a comfortable life for your fish. It is especially necessary for tropical species, where the water temperature should be at least 22 and no more than 30 degrees. It is often believed that an aquarium water heater is a simple and optional device. Although in importance it is equal to a water filter.

Previously, salt heaters were most often found. They functioned by passing electricity through the solution. But consumers had to independently regulate the level of saline liquid. Therefore, this type gradually became a thing of the past. At the moment, there are a large number of different devices for heating water in a fish house.

Types of water heaters

There are various devices for heating water in an aquarium. Basically, they can all be divided into four main types. Firstly, these are submersible models. They have several subtypes:

• Glass. The device body is shock-resistant and heat-resistant. It closes hermetically. It turns on and off automatically, while maintaining the set temperature.
• Plastic. Technically advanced heater compared to glass. It has compact dimensions, flat shape and LED signal.
• Model with titanium heating element. Can be used for any aquarium. Perfect for heating large volumes of water, for example, if you keep turtles rather than fish.
• Mini heaters. They are characterized by a flat design, which allows you to hide such a device even under the ground in an aquarium.

Secondly, it is available for sale for an aquarium. Mainly used for external filters, which allows you to leave more space in the aquarium itself. A vertical filter return hose is attached, which allows the heat to be distributed evenly. Thirdly, you can buy heating cables for heating water. They also provide a smooth supply of heat, pass along the bottom, and are attached using suction cups. Fourthly, it is possible to use They can be located under the aquarium. Provide smooth heat dissipation.

Making a water heater at home

Sometimes it is not possible to purchase even the simplest device for heating water. In this case, you should make a water heater for these purposes. There are many in various ways. Let's look at one of them step by step:

1. First you need to find a container that can withstand temperature changes and not burst. A regular glass medicine bottle may work. To check, place it in a container of water at room temperature, holding it with tweezers. Pour boiling water: if there is no damage, you can use such a container.
2. The heater may have one or more resistors connected in series. In this case there will be several of them. We prepare resistors for placement. You can make a kind of valve to prevent sand from getting outside the heating part.
3. If desired, you can solder the LED. It will signal that the heater is turned on.
4. We check whether the part responsible for heating is working. To do this, briefly plug in the device and check the temperature of the device. Place the resistors in the prepared container. Just fill it with sand or salt first.
5. We take a heat gun or glue for gluing aquariums. And we fill all the remaining space in the water heater.
6. For ease of fastening, you can purchase a suction cup. You just need to remove the hook from it.
7. Using fishing line, attach the suction cup to the heater.

That's all the steps that are required to self-made device for heating water in an aquarium. If you are not ready to take on the work yourself, it is better to contact specialized stores. The choice is very varied: you can buy one or another water heater for an aquarium. The price will vary depending on the type, power and manufacturer. Typically the cost varies from 800 to 2,000 rubles.

Popular brands of aquarium water heaters

When you come to a pet store to purchase a water heating device, the question arises: which model is better? As practice shows, purchase better water heater for aquariums from well-known and trusted brands. Leading manufacturers of such devices include products from Aquael, Eheim, Hagen, JBL, Tetra and Xilong.

Thus, the water heater has long conquered the markets, thanks to its good price-quality ratio. Mostly model range glass and plastic models are replenished. To optimize the use of such a device, the manufacturer suggests installing control buttons and a built-in electronic thermometer on plastic water heaters.

Eheim offers rod-shaped water heaters. Thanks to the glass body and full immersion The water is heated evenly. And a manufacturer of aquarium thermostats, such as Tetra, equips the device with an additional device. Such devices operate effectively in automatic mode.

How to choose the right water heater for you?

Let's say you decide to buy a water heater for an aquarium. How to choose it? It’s worth thinking about this in advance so that when you come to the store you already know exactly what you want. You should pay attention to the length, which should correspond to the water level in the container. Domestic heaters are all the same in length. If you purchase a model without automatic adjustment, you will have to calculate the temperature so that the water does not overheat in hot weather. Or you can install two such devices and turn off one of them in summer weather.

There are two opinions regarding the advisability of using an automatic temperature controller. Some believe that the liquid should change its thermal regime at different times of the day, as in its natural environment. Automation cannot provide this. Others, on the contrary, are sure that the aquarium should have a constant temperature.

In order not to make a mistake with the power, it is better to choose a more powerful water heater for an aquarium, with automatic adjustment. This way you can set the heating to turn off when a certain temperature is reached. In this case, be sure to pay attention to the quality and, accordingly, to the manufacturer.

What information will you find in the instructions for use for the water heater?

Besides technical characteristics device, which can be found in the instructions for use for the water heater, it is worth considering the recommendations for installing and adjusting the device. When you purchase a water heater for an aquarium, how to install it correctly will be described in the instructions. There you can find the following recommendations: The device can be completely submerged in water as it is waterproof. Do not install the heater in gravel or sand. Don't forget also about the decrease in water level due to evaporation. The water heater must be fixed in a place where constant and uniform circulation of water is ensured. Special attention give next moment: Only 15 minutes after lowering the device into the water can you connect it to the network.

Recommendations for adjustment are as follows: you need to wait until the heater warms up a little - to the temperature of the surrounding water. Only after this should it be turned on. When the indicator light is on, it means that the device is turned on. Further recommendations will be different depending on the presence or absence of automatic adjustment. Read the instructions before installing the device. Important Tips for a specific model will be indicated there.

The time has come when you want to buy a beautiful aquarium. There are many devices technical means to keep and maintain aquarium inhabitants in an aquarium close to their real life conditions.

The main tools in an aquarium to maintain the conditions that aquarium fish need are: an aquarium heater, a compressor, a filter, lighting and oxygen. The question immediately arises: how to install a heater in an aquarium?

Below in the article we will look at how to choose and then install the optimal heater for your aquarium. You can buy an aquarium heater, filter and compressor in any store that specializes in sales aquarium fish. In the future, you will not have to place the aquarium near it.

1 How to choose the right aquarium water heater

You can't do without a heater and compressor. The heater maintains the desired water temperature, and the compressor supplies oxygen to the aquarium fish.

Among novice aquarists, the question arises of how powerful an aquarium water heater should be, and what reasons affect the water temperature in the aquarium:

Approximately 0.6 W of aquarium heater power per liter of water. Also when choosing aquarium heater There are several factors to consider:

• What is the room temperature, where is your aquarium located;
• Drafts in the room;
• What shape is your aquarium, its capacity;
• Placing an aquarium in the house;
• The presence of a lid on the aquarium and lighting.

The aquarium heater is selected in accordance with the above factors. The main thing in an aquarium heater is its power, which is selected in accordance with the size of the aquarium.

If you decide to purchase an aquarium heater with a thermostat, then it is better to buy it with a power reserve, from a good, trusted manufacturer.

Today there are many companies and manufacturers producing aquarium heaters:

• Aquarium water heater JBL (JBL) ProTemp S 150, 150 W– manufactured with a 150 W thermostat. The thermostat is covered with a plastic casing to prevent aquarium inhabitants from getting burns. When this heater is removed from the water, the protection is triggered and the heater is immediately turned off. The price of a heater for an aquarium of this type will cost you from 1000 rubles and more.

• Aquarium heater Resun (Resan) SUNLIKE 50 — consists of a quartz case with a two-layer coating. It has an automation system. When using this aquarium heater, it is completely immersed in water. When the desired temperature is set, the heater turns itself off. When the water temperature in the aquarium drops, the heater automatically turns on itself. The price of a water heater for an aquarium of this type will cost you from 500 rubles and more.

• Aquarium heater Aquael- produced with gold-plated contacts. These contacts increase the service life of the aquarium heater. It has power adjustment, with which you can set any temperature in your aquarium. It has a beautiful black body that does not spoil the appearance in the aquarium. It can be used in both freshwater and marine aquariums. On average, the price of an aquael aquarium heater will cost you from 720 rubles and more.

2 Types of heaters for aquariums.

Today there are many types of aquarium heaters. Here are a few of them:

Submersible water heater for aquarium – this type ensures uniform and constant heating of water in the aquarium.

A submersible water heater circulates water in your aquarium, thereby creating an aquifer. Such heaters are easy to control and use. They easily connect to the thermoregulation system.

This heater must be used by immersing it completely in water. This type is attached using ordinary suction cups and has a silicone winding. Due to this, their service life increases.

Important!!! It is strictly forbidden to turn on the aquarium water heater without immersing it in water.

Instantaneous water heater for aquarium - works as follows. This type of heater passes a flow of water through itself. This type of heater contains a special heating element that heats the water.

In other words, it turns on automatically when water flows through it. In this heater, the most important thing is the heating element, which must be of high power.

The disadvantage of this flow heater for an aquarium is that it consumes a lot of energy. Buy an aquarium heater of this type, you can from 2740 rubles and above.

You must purchase a thermometer for your aquarium heater. Today there are possible types of thermometers. The most optimal would be a mercury thermometer, which is installed in a vertical position on the other edge of the aquarium from the heater. There are also electronic thermometers that are equipped with a sound signal.

Recently, liquid crystal thermometers have begun to be used. It looks like a regular ruler with a scale. The downside of this thermometer is its inaccurate reading of water temperature. We do not recommend using such thermometers.

2.1 Maintenance of aquarium heaters

Over time, aquarium water heaters begin to not heat the water well enough, and dirt begins to appear on them.

To prevent this from happening, you need to periodically clean the aquarium heater. To do this, you do not need to completely disassemble the heater. First of all, when cleaning an aquarium heater, you need to disconnect it from the electrical network.

After this, the heater body can be cleaned with a regular hard sponge. If there are boiler stones on the heater, remove them special means. After this, the heater is washed running water and put back into the aquarium. This procedure must be done every two months.

2.2 Aquael aquarium heater review - video

The most important condition for the favorable functioning of your aquarium is maintaining a certain temperature that is optimal for a particular type of fish. Typically, fish need a temperature of 22 to 32 degrees, depending on their species.
Until recently, aquarists actively used simple
heaters. In some specialized stores Heaters are still sold, but purchasing them is not recommended. Now the blessed era of thermostats has arrived. The power of thermostats depends on how large the aquarium is. Experts recommend a power of 1.5 watts per 1 liter of water. For example: a 100 liter aquarium will require a 150 watt heater.
Fish owners should also know that the colder the room, the faster the water in the aquarium cools, and the greatest cooling occurs in aquariums with a large area of ​​​​its walls.

Therefore, it is best to purchase heaters “with a reserve”, i.e., more powerful ones. Such heaters easily and quickly cope with temperature drops, operate smoothly, without overheating, and last much longer. But powerful heaters must be of high quality.
It would also be useful to know that the cost of a heater does not particularly depend on its power, and neither does energy consumption. The whole question is the reliability of the device, i.e., the thermostat and the heating element. If the thermostat of a powerful heater breaks down, the inhabitants of the aquarium have two little comforting options - to die either from the cold or from unusual high temperature water. Some, in order to avoid such sad consequences, purchase 2 medium-power heaters. If one thermostat fails, another will maintain the optimal living environment. If one of the thermostats breaks down, the water will not reach critical temperature, and the fish will be fine in the end. But, as you know, good things don’t come cheap. A couple of high-quality heaters will cost you twice as much as one simple one. The right to choose is yours.

Using a water heater

Heaters are manufactured in accordance with currently valid safety standards. The heater may only be turned on when electrical network with the parameters corresponding to those indicated on the heater itself and its packaging. It is forbidden to turn on the heater when it is removed from the water. Before each operation related to the heater, you MUST DISCONNECT the voltage. Before you put your hand in the water, make sure that the heater and all electrical appliances in the aquarium are UNCONNECTED from the mains. Do not use a damaged heater or a heater with a damaged wire. The connecting wire must not be changed or repaired; in this case, the entire heater must be replaced. Also DO NOT MOUNT A SWITCH on a wire.
The water level must always be above the minimum immersion level, the MINIMUM WATER LEVEL mark marked on the heater body. The maximum immersion depth of the heater is 80 cm. The heater is intended for use only in enclosed spaces and exclusively in aquariums.

How to install a heater in an aquarium

The heater is waterproof, and it can be installed in the aquarium both in a vertical position - with the adjustment handle located above the water surface, and in a horizontal position - completely submerged. Do not insert the heater into sand or gravel. The water level must always be above the minimum immersion level, the MINIMUM WATER LEVEL mark marked on the heater body. It is necessary to remember that the water level is constantly decreasing as a result of evaporation. The heater is attached to the wall of the aquarium using a bracket with two suction cups, which should be attached to the heater directly below the head. The heater must be fixed in the aquarium in a place where there is constant and uniform circulation of water. ATTENTION! Only about 15 minutes after installing the heater in the aquarium, when the temperature of the bimetallic switch in the heater becomes equal to the temperature of the water in the aquarium, can the heater be connected to the power supply.

Types of Aquarium Heaters

To be able to create as much as possible comfortable conditions For the habitat of fish and plants, special devices are used - aquarium heaters. There are several types of them, but the principle of operation is the same for all - electrical heating of the element in a sealed environment. The most commonly used heaters are:

Submersible(plastic, glass, titanium). It consists of a heating element built into an impact-resistant, heat-resistant housing in the form of a flask or elongated cylinder, and is designed to be lowered into an aqueous environment.

Flow-through. It has a plastic body and is mounted in a vertical position on the return hose of an external filter, which saves internal space and creates a flow of warm, aerated water.

Heating cables. They are installed under and allow you to evenly heat the entire aquarium and create additional water circulation.

Heating mats. They are rectangular mats that are installed under the aquarium. The heat generated passes evenly through the bottom and increases the temperature of the water.

DIY aquarium heater

When making such a device, you need to remember that the operating conditions are associated with a serious risk of electric shock.

But if the decision is made in favor of a handicraft, then there is good option with the creation of a structure from resistors (resistances), a piece of glass tube with thick walls, dry filler and remote thermostat. Installation work occurs in the following order.

1. The power of the heating element is determined based on a special table, which takes into account the difference in temperature between that required in the aquarium and room temperature. Calculated required strength current by dividing the selected power by the applied voltage. By dividing the voltage used by the calculated current, you can obtain the resistance value of the heater. Selected required quantity identical resistors so that their total power and resistance indicator corresponds to the calculated values.

2. The length and diameter of the glass tube are determined based on the size and number of resistances.

It is important that the resistors soldered in series are placed in the tube with a free space of 15 cm.

3. Cleaned and calcined sand can be used as a filler.

4. The bottom of the glass tube is closed with a suitable rubber stopper placed on the aquarium sealant.

5. The ends of the network cable are soldered to the upper and lower resistors . The entire structure is placed in a tube and covered with sand. It is important that the sand is at the bottom of the tube and covers the top resistor.

6. The top of the tube is carefully sealed with aquarium sealant. The power cable is connected to a thermostat with a remote temperature sensor, which in turn is placed in the aquarium.

7.The heater is placed vertically in such a way that the part of the tube containing the resistors is hidden under water. The structure is attached to the wall of the aquarium using special suction cups.

Schemes for manufacturing the thermostat itself based on a comparator and thermistors have also been developed.

Aquarium heater with thermostat

The main inconveniences when using the heater are related to with the need to constantly monitor its work. Even having reached the desired water temperature, the device still continues to function and must be disconnected from the network manually.

To get rid of this problem, a special device is used - a thermostat, which is a device with a built-in temperature sensor. It allows you to turn off the heating element when a preset value is reached and turn it on again when the water begins to cool.

This ensures a stable microclimate without temperature changes. Application modern technologies allows the production of very compact and easy-to-use thermostats.

According to manufacturing technology, they are divided into two types.

Electronic. Possess high accuracy(most of them are equipped with an information board). Disadvantages include the relative high cost and lack of reliability.

Mechanical. They are found most often, are characterized by stability and reliability during operation, and are cheaper in price. They often distort real readings by several degrees, so to accurately adjust the device, you must use a separate thermometer.

According to the level of safety during operation and durability of the devices, thermostats are divided into:

• Remote - located outside the aquarium, not subject to the influence of the aquatic environment and the waste products of aquatic organisms. This increases their service life and makes it possible to use cheaper heaters and replace them without additional costs. To determine the operating mode, a separate temperature sensor is used, which is located in the aquarium and connected by a wire to the thermostat.

The latter type of design is the most popular among aquarists and is often made in the form of an elongated glass flask, inside which is located electric heater and a thermostat. For greater thermal conductivity, the space of the flask is filled with the smallest ceramic filler.

The tightness of the structure is ensured by a rubberized or plastic cap through which the power cord passes. There is also a regulator here that allows you to set the required temperature.

Well-known brands - Eheim, Fluval, Ferplast, Aquael, Tetra - produce reliable and high-quality submersible heaters for aquariums with a power thermostat from 25 to 300 W. Such devices are capable of providing necessary conditions in aquariums up to 1500 liters.

To reduce the likelihood of water overheating, there is a practice of simultaneously using several less powerful thermal devices.

In case it is not possible to purchase necessary equipment, you can do it yourself.

Our selection of the three best aquarium heaters from Aliexpress

Aquarium heater 25 W/300 W

This heating rod can provide the right warmth and maintain the temperature of the water inside the tank. It can automatically adjust the temperature as needed for the fish in the aquarium.

Peculiarities:
The temperature scale can be adjusted between 20~34℃(68~93°F).
Fully submersible, waterproof double insulation, durable and safe design.
Power indicator, ensures safe operation.
Can automatically adjust the temperature, good for fish in aquarium.
Specifications:
Color: black
Material: Glass
Plug: EU plug
Power: 25W/50W/100W/200W/300W (optional)
Voltage: 220-240 V
Frequency: 50/60 Hz
Temperature Range: 20~34℃/68~93°F
Item Length:
25W: 20.5cm/8in
50W: 21cm/8.27in
100W: 25.5cm/10in
200W: 29cm/11.43in
300W: 29cm/11.43in
Cable length: approx. 85cm/33.5in
Package Size:
25W: 26.5*7*4cm/10.4*2.76*1.57in (L*W*H)
50W: 26.5*7*4cm/10.4*2.76*1.57in (L*W*H)
100W: 30.5*7*4cm/12*2.76*1.57in (L*W*H)
200W: 36.5*7*4cm/14.4*2.76*1.57in (L*W*H)
300W: 36.5*7*4cm/14.4*2.76*1.57in (L*W*H)
Package Weight: 170g~230g/6oz~8.1oz
Note:
1. This item is only suitable for fresh water.
2. The heating rod must be completely immersed in water
3. When the indicator is on, it works.
4. Before cleaning the fish tank or heating rod, please turn off the power for 15-20 minutes to cool down the heating rod.
Package list:
1 * Heating Rod

Price: 664.37 - 819.62 rub. / piece

Special price:

418.29 - 516.59 rub. / piece

Stainless Steel Aquarium Heater with LCD Digital Thermometer

Ideal Aquarium Temperature Controller Kit Consists of: Stainless steel Water heater and LCD immersion thermometer.
Both are fully submersible, waterproof double insulation, durable and safe design.
With the easy-to-read LCD display for this thermometer, you can easily keep track of the temperature in your aquarium.
The convector will turn off automatically when the temperature is reached. A sensitive and reliable thermostat maintains an even temperature.
Parameters:
Heater:

Model: immersion heater for aquarium

Material: Stainless steel

AC input: 220V, 50Hz

Power: 50W, 100W, 200W, 300W, 500W

Temperature range: 16-32 degrees Celsius

Heater Length: 16cm/29cm/29cm/35cm/35cm

Protective cover: 6 parts, free stitching, adjustable length 15-42 cm.

Aquarium Suit:
50W: less than 50L water, about 20x30cm
100W: 50-100L water, about 40×60cm

200W: 100-200L water, about 60x80cm

300W: 150-300L water, about 80×100cm500W: 250-500L water, about 130×150cm
Thermometer:
Color: Black + Silver

Material: ABS plastic
Display: LCD digital display
Temperature range: 0°C to 50°C
Default alarm setting: maximum: 28°C; lowest: 18 °C
Power: 1*1.5V AG13 Button Battery (Not included)
Sucker Diameter: 3cm/1.2in
Product size: 50 * 30 * 20mm / 1.97 * 1.2 * 0.8in
Item Weight: 26g/0.92oz
Package:
Voltage: 220-240V 50Hz
LCD display
Adjustable temperature: 20 to 35 degrees
External design, work with filter cup
Automatic shutdown when there is no water flow insid
Note:
Connect the heater to the inner tube of the filter cup
The direction of the arrow on the heater should be the same as the direction of the water flo
Package includes:
1 x heater
2x17mm adatper for inner diameter 16mm water hose
2x22mm adapter for 20mm inner diameter water hose

Price: RUB 2,325.29 / piece

Conclusions

There is a theory according to which aquatic organisms must be kept in conditions as close as possible to natural ones. Temperature changes in nature occur constantly, and there seems to be no particular need to use an aquarium heater.

But in practice it has been proven that fish and plants feel much better, get sick less and live longer in a stable microclimate. This is why using an aquarium heater with a thermostat, especially during the cold season, is more than justified.

The beauty of an aquarium depends not only on its choice and design, but also on how colorful its inhabitants are. It is useful to remember that the most colorful and unusual aquatic inhabitants live in tropical and equatorial waters. And their habitats are distinguished not only by their abundance various types and palm trees on the banks, but also because environment Such creatures are noticeably warmer than our everyday life, even at the height of summer. To create ideal conditions For your charming pets, the water in the aquarium must not only be purified and oxygenated, but also heated. This task is performed special device- aquarium heater.

Aquarium heater: how does it work?

Setting up a water heater for an aquarium is not difficult. His main element- a special wire that heats up under the influence of electricity. To make its use safe, the wire itself is located on a ceramic core, and is protected from contact with water by an outer casing made of glass or plastic.

If glass is chosen for the body, it is usually heat resistant and is also closed with a special lid that ensures tightness. The cover is also used to place all the control elements of the device.

Plastic models are compact and the price is slightly higher. But this is more than justified: such a heater not only looks stylish thanks to a body made of unbreakable plastic, but is also more advanced from a technical point of view.

When choosing a heater for an aquarium, you need to remember that the larger the volume of water, the more powerful the device you need to buy - otherwise it simply will not cope with its task.

Aquarium heater: how to monitor the temperature?

Accuracy of compliance temperature regime – important element long and comfortable life every inhabitant of the aquarium water world. However, monitoring your temperature on your own is not only tedious, but often impossible. In order not to waste your time and attention, you need to purchase an aquarium heater (heater) with a thermostat.

Heaters of this type are equipped with a special sensor that constantly monitors the water temperature. As long as this temperature is within the range useful for pets, the aquarium heater works quietly and creates a cozy environment for them. But as soon as the temperature exceeds the limit set by the owner, the device detects this and turns off, allowing the water to cool to the desired level.

Thermostats can be mechanical or electronic. The most common are mechanical ones - they are distinguished by high level reliability, a little more low prices and stable operation. However, their work requires periodic inspection– they can distort the readings by several degrees, and you need to check them with a separate thermometer. Electronic models are more accurate, so they have a higher price, but they are also a little less reliable.

In addition, the thermostat with which the aquarium heater is equipped can be remote or built-in. The remote one is located mostly outside the aquarium - only the temperature sensor is immersed in the water. However, it did not become widespread, since the built-in models turned out to be much more practical and convenient. They are collected in a single building with heating element, becoming compact and distinguished by an advantageous design in the form of an elongated glass flask.