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Hydor Theo 300W (UL) Submersible Aquarium Heater, 300 Watts, As Shown

Hydor Theo 300W (UL) Submersible Aquarium Heater, 300 Watts, As Shown

Hydor THEO (UL) Submersible Aquarium Heater - High Quality Fish Tank Water Heater and Aquarium Water Heater SelectionKeep your aquarium at the perfect temperature with the Hydor THEO (UL) Submersible Aquarium Heater. This sleek fish tank water heater... more

$37.99

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Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

300W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 53-80 gallons.Length - 15.5 Part #: AHY00037Item Name: Theo... more

$34.61

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Peazz

(100+)
Best Seller
Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

300W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 53-80 gallons.Length - 15.5 Part #: AHY00037Item Name: Theo... more

$34.61

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Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

300W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 53-80 gallons.Length - 15.5 Part #: AHY00037Item Name: Theo... more

$34.61

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Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

Hydor Usa Inc. Theo 300 Watt Submersible Shatterproof Heater 15.5" Hy00037

300W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 53-80 gallons.Length - 15.5"Part #: AHY00037Item Name: Theo... more

$25.95

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Hydor 25W Submersible Glass Aquarium Heater - Original Theo

Hydor 25W Submersible Glass Aquarium Heater - Original Theo

Theo Heater. New aquarium heater functioning with the exclusive PTC technology means that this heater will not break or damage when run out of the tank. Theo aquarium heater has all the necessary feature for safe and precise temperature maintenance of... more

$17.84

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Theo Heater 150 watt

Theo Heater 150 watt

"Patented heating element automatically turns off if water level declines Easy temperature adjustment - knob clicks at every degree change Submersible heater with shatterproof glass resists breakage Patented heating film and special shatterproof glass... more

$24.99

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(275,000+)
"ETH In-Line Heater 200 watt, 5/8"""

"ETH In-Line Heater 200 watt, 5/8"""

"Prevents temperature variations caused by poor water circulation Precise, accurate temperature setting Indicator light shows when unit is ""ON"" Double insulated and double sealed The first compact aquarium heater that operates externally, saving... more

$54.99

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(275,000+)
"Cobalt Aquatics Neo-Therm Heater 300W, 10-7/8"" long x 2 (Mfg# 31007)"

"Cobalt Aquatics Neo-Therm Heater 300W, 10-7/8"" long x 2 (Mfg# 31007)"

"Flat, narrow design provides sleek, subtle aquarium heating. Within the stylish exterior of the Cobalt Aquatics Neo-Therm Heater lies a sophisticated electronic microprocessor thermostat to ensure aquarium temperatures accurate within +/-0.5°F.... more

$140.27

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(275,000+)
Hydor ETH 300 In-Line External Aquarium Heater, 300w, 5/8" hose

Hydor ETH 300 In-Line External Aquarium Heater, 300w, 5/8" hose

ETH Heaters are the first external heaters for aquariums with the exclusive PTC technology. The self-limiting PTC heating element guarantees maximum safety against any risk of overheating. Designed to be used on return lines coming from canister... more

$49.84

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Hydor 200W Submersible Glass Aquarium Heater - Original Theo

Hydor 200W Submersible Glass Aquarium Heater - Original Theo

Theo Heater. New aquarium heater functioning with the exclusive PTC technology means that this heater will not break or damage when run out of the tank. Theo aquarium heater has all the necessary feature for safe and precise temperature maintenance of... more

$23.79

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In Line Heater Eth 300W 53-80G

In Line Heater Eth 300W 53-80G

Easy to connect to any canister filter, the ETH External In-Line Heater is suitable for both freshwater and marine aquariums. Installs vertically on the return line of a canister filter or sump, allowing for better heat distribution as water returns to... more

$104.95

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150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (500 Watt 1/2'(12/16mm) Hose)

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (500 Watt 1/2'(12/16mm) Hose)

Features:1. Thermal spraying glass, speed up the heating process, higher efficiency. 2. External design, easy to install and doesn't occupy space in the tank. 3. Two sensors to exam the temperatures of water inlet and outlet. 4. Auto power off safety... more

$63.99

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150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (300 Watt 5/8' (16/22mm) Hose)

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (300 Watt 5/8' (16/22mm) Hose)

Features: 1. Thermal spraying glass, speed up the heating process, higher efficiency.2. External design, easy to install and doesn't occupy space in the tank.3. Two sensors to exam the temperatures of water inlet and outlet.4. Auto power off safety... more

$59.99

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Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

100W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. Extremely compact at 8.9 . For aquariums 14-26 gallons.Length - 8.9 Part... more

$33.36

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Peazz

(100+)
Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

200W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 26-53 gallons.Length - 12 Part #: AHY00036Item Name: Theo... more

$34.61

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Peazz

(100+)
In Line Heater Eth 300W 53-80G

In Line Heater Eth 300W 53-80G

Easy to connect to any canister filter, the ETH External In-Line Heater is suitable for both freshwater and marine aquariums. Installs vertically on the return line of a canister filter or sump, allowing for better heat distribution as water returns to... more

$104.95

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Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

200W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 26-53 gallons.Length - 12 Part #: AHY00036Item Name: Theo... more

$34.61

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Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

100W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. Extremely compact at 8.9 . For aquariums 14-26 gallons.Length - 8.9 Part... more

$33.36

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Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

100W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. Extremely compact at 8.9". For aquariums 14-26 gallons.Length - 8.9"Part... more

$24.95

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Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

200W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 26-53 gallons.Length - 12 Part #: AHY00036Item Name: Theo... more

$34.61

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Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

Hydor Usa Inc. Theo 200 Watt Submersible Shatterproof Heater 12" Hy00036

200W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. For aquariums 26-53 gallons.Length - 12"Part #: AHY00036Item Name: Theo... more

$25.95

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Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

Hydor Usa Inc. Theo 100 Watt Submersible Shatterproof Heater 8.9" Hy00035

100W submersible aquarium heater. UL listed. Safe and reliable. Made from specially enginereed shatterproof glass. Temperature controlled and maintained by precise micro-switch. Extremely compact at 8.9 . For aquariums 14-26 gallons.Length - 8.9 Part... more

$33.36

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Slim Heater for Bettas, Bowls and Aquariums, All Types Internal Skimmer Mount your Aquariums Aquarium Helps HCX9115E Theo InLine 10 promoting 58 Small ideal Heater.., By Hydor

Slim Heater for Bettas, Bowls and Aquariums, All Types Internal Skimmer Mount your Aquariums Aquarium Helps HCX9115E Theo InLine 10 promoting 58 Small ideal Heater.., By Hydor

Helps guarantee your fish a healthy life by promoting the ideal water temperatureCan be positioned under gravelPlug and playNo temperature to set90-Degree Angle for perfect betta bowl fit more

$17.69

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Hydor Theo Heater 400 Watt for 80-105 Gallons

Hydor Theo Heater 400 Watt for 80-105 Gallons

Theo reservoir & aquarium heaters have all the necessary features for safe and precise temperature maintenance of the water in your tank or reservoir. The exclusive technology and the high quality of the components guarantee a long lasting product. more

$25.95

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THEO Heater - 300W - Up to 80 gal.

THEO Heater - 300W - Up to 80 gal.

Provide your tank with the proper temperature with the most advanced heating technology available. THEO heaters are designed with a peculiar cylindrical shape that renders them virtually shatterproof. Fully submersible; THEO heaters function with the... more

$33.39

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300W Best Digital Aquarium Heater Fish Tank Tater Heater Aquarium Thermometer

300W Best Digital Aquarium Heater Fish Tank Tater Heater Aquarium Thermometer

100W/ 200W/ 300W Adjustable Aquarium Fish Tank Water HeaterIt has afety guard design that can protect your fish from the heating core more

$20.19

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Fish Tank Submersible Water Adjustable Aquarium Heaters, Set of 2

Fish Tank Submersible Water Adjustable Aquarium Heaters, Set of 2

25W 50W 100W 200W 300W Aquarium Heater Fish Tank Submersible Water AdjustableThese Aquarium Glass Submersible Heaters guarantee safe, easy and precise temperature control of your aquarium. They are ideal for keeping your fish happy and comfortable with... more

$14.99

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ETH 300 In-Line Heater for 16mm or .625 in. Tubing - 300W

ETH 300 In-Line Heater for 16mm or .625 in. Tubing - 300W

The ETH external In-Line heater uses the advanced PTC system; which is a special polymer sheet; silk-screened with heating ink (like your car's windshield defroster) instead of metal coils. This state-of-the-art system allows the unit to be left... more

$55.95

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THEO Heater - 150W - Up to 40 gal.

THEO Heater - 150W - Up to 40 gal.

Provide your tank with the proper temperature with the most advanced heating technology available. THEO heaters are designed with a peculiar cylindrical shape that renders them virtually shatterproof. Fully submersible; THEO heaters function with the... more

$29.99

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Aqueon Submersible Aquarium Heaters 300W

Aqueon Submersible Aquarium Heaters 300W

Aqueon features a variety of accessories to help keep your fish and their aquatic environment clean and healthy. Aqueon introduces the most accurate, reliable, durable and easy to use aquarium heaters on the market. Available in five sizes/wattages to... more

$25.99

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Hydor 400W Submersible Glass Aquarium Heater - Original Theo

Hydor 400W Submersible Glass Aquarium Heater - Original Theo

Theo Heater. New aquarium heater functioning with the exclusive PTC technology means that this heater will not break or damage when run out of the tank. Theo aquarium heater has all the necessary feature for safe and precise temperature maintenance of... more

$26.65

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"ETH In-Line Heater 200 watt, 1/2"""

"ETH In-Line Heater 200 watt, 1/2"""

"Prevents temperature variations caused by poor water circulation Precise, accurate temperature setting Indicator light shows when unit is ""ON"" Double insulated and double sealed The first compact aquarium heater that operates externally, saving... more

$54.99

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(275,000+)
Hydor 7.5w Slim Heater for Bettas and Bowls, 2 to 5 gal

Hydor 7.5w Slim Heater for Bettas and Bowls, 2 to 5 gal

Hydor 7-1/2-watt Slim Heater helps guarantee your fish a healthy life by promoting the ideal water temperature. Specially designed with the innovative PTC (Positive Thermal Coefficient) element to heat the temperature of your aquarium or terrarium an... more

$6.49

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Theo Heater 100 watt

Theo Heater 100 watt

"Patented heating element automatically turns off if water level declines Easy temperature adjustment - knob clicks at every degree change Submersible heater with shatterproof glass resists breakage Patented heating film and special shatterproof glass... more

$21.99

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(275,000+)
Finnex TH Series Titanium Heating Tubes 300W Heater w/Guard (Mfg# TH-0300S)

Finnex TH Series Titanium Heating Tubes 300W Heater w/Guard (Mfg# TH-0300S)

"Titanium heaters upgraded with added safety and greater installation ease. Finnex TH Series Titanium Heating Tubes feature a protective heater guard that encases the heating element to safeguard aquarium inhabitants as well as surrounding equipment.... more

$43.99

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(275,000+)
150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (150 Watt 5/8' (16/22mm) Hose)

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (150 Watt 5/8' (16/22mm) Hose)

The ISTA External Heater is easily installed by cutting the tubing and connecting the two parts of the tube to each side of the ISTA External Heater.For reduced maintenance, it is recommended that the ISTA External Heater be installed within the... more

$49.96

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150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (300 Watt 1/2'(12/16mm) Hose)

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (300 Watt 1/2'(12/16mm) Hose)

Features: 1. Thermal spraying glass, speed up the heating process, higher efficiency.2. External design, easy to install and doesn't occupy space in the tank.3. Two sensors to exam the temperatures of water inlet and outlet.4. Auto power off safety... more

$63.99

FREE shipping

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150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' 300 Watt 5/8' (16/22mm) Hose

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' 300 Watt 5/8' (16/22mm) Hose

150w/300w/500w In-Line External Heater AQUARIUM HEATER - 150/300/500 WATT 1/2-5/8in Size:300 Watt 5/8in (16/22mm) Hose Features: 1. Thermal spraying glass, speed up the heating process, higher efficiency.2. External design, easy to install and doesn't... more

$84.45

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150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (500 Watt 5/8' (16/22mm) Hose)

150w/300w/500w In-Line External Heater Aquarium Heater - 150/300/500 Watt 1/2'-5/8' (500 Watt 5/8' (16/22mm) Hose)

Features:1. Thermal spraying glass, speed up the heating process, higher efficiency.2. External design, easy to install and doesn't occupy space in the tank. 3. Two sensors to exam the temperatures of water inlet and outlet. 4. Auto power off safety... more

$66.99

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