Penn-Plax Cascade Heat 300W Preset Submersible Aquarium Heater, 12-in

$19.90 (-57%) Chewy Price
$45.99 List Price
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About This Item

Details

  • Designed to maintain tank temperature within 1 degree of accuracy.
  • Temperature gauge is visible, accurate, and easy to adjust.
  • Heater is fully submersible, and it can be placed horizontally or vertically in your tank via dual suction cups.
  • Comes preset to 76 degrees Fahrenheit, but it can be manually reprogrammed to any temperature.
  • Easy to use and install!

Penn-Plax Cascade Heat Aquarium Heaters

The Penn-Plax Cascade Heat Aquarium Heater series delivers accurate and dependable temperature control for both freshwater and saltwater aquariums. With an adjustable temperature range of 68°F to 89°F, they ensure a stable environment for your fish.

Quality You Can Trust

Penn-Plax takes pride in producing reliable, accurate heaters every time. With a visible and accurate temperature scale and an orange pilot light to indicate the heating cycle, you’ll have confidence knowing your aquarium is in safe hands.

Easy to Adjust and Maintain

The user-friendly red control knob makes temperature adjustments straightforward. Rotate counterclockwise to increase and clockwise to decrease, following the + and – symbols for guidance. The suction cup mounting system makes installation easy, too.

Safety First

Cascade Heat Aquarium Heaters are specifically designed for full submersion. Always remember to disconnect the heater from the power supply during water changes to ensure the safety of both your fish and the equipment.

About Penn-Plax

Since 1956, Penn-Plax has been making high-quality pet supplies for animals of all sizes. The brand is synonymous with innovation and quality and known for always prioritizing the wellbeing of pets.

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Questions & Answers

2 Customer Questions


what is the preset tempeture on this heater?

Answer by ChewyOct 24, 2022
This aquarium heater comes preset to 76 degrees Fahrenheit, but it can be manually reprogrammed to any temperature.

For how many gallon is the Penn-Plex Cascade 300w Heater?

Answer by ChewySep 22, 2022
It is safe to use in both freshwater and saltwater tanks up to 40 gallons in size.
3.4
Rated 3.4 out of 5 stars
26 Ratings

12 Customer Reviews



Rated 5 out of 5 stars
By Robert on Jan 15, 2025

Can’t beat it.

For the price you can’t beat this heater especially if you have larger tanks or tanks that are outside year round.

For the price you can’t beat this heater especially if you have larger tanks or tanks that are outside year round.


Rated 1 out of 5 stars
By Tom on Nov 9, 2024

Blew up

Emptied the water out of the tank. And the glass blew up.

Emptied the water out of the tank. And the glass blew up.


Rated 1 out of 5 stars
By ShadesofGRAY on Mar 2, 2024

the temperature set is not acurate.

I bought this heater for my 55gal aquarium, I have sensitive fish in the tank. They are all now being effected as the heater is set for 82 but the light indicating

I bought this heater for my 55gal aquarium, I have sensitive fish in the tank. They are all now being effected as the heater is set for 82 but the light indicating when its on goes off at 74. I hope my fish are alright till I get another heater. This is unexpectable, especially considering the amount of money these fish are worth let alone the fact they are a pet i dont wanna lose.


Rated 1 out of 5 stars
By Hal on Sep 17, 2023

Heater never worked right

Bought this heater since it was the same size as the other 3 I am still using with no problems. This one just never warmed the water up the same tho despite being

Bought this heater since it was the same size as the other 3 I am still using with no problems. This one just never warmed the water up the same tho despite being just as big of a heater. I actually have it in a smaller tank, turned up all the way, and the water is semi-warm at best. Then today it just decided to give out, after only being used for a few months. Stick with another brand for your aquarium heater, this one just didn't do the trick at all and then stopped after a few months.


Rated 2 out of 5 stars
By Rudy on Oct 25, 2023

Only use if short on cash

Cheap heater. Worked for a year for Me but does not work well. Be careful because temp settings don’t work correctly. I would not purchase again.

Cheap heater. Worked for a year for Me but does not work well. Be careful because temp settings don’t work correctly. I would not purchase again.


Rated 2 out of 5 stars
By Courtney on Apr 23, 2023

Quit working within a couple of months

Just as the header says. Stopped working after a couple months. It’s the recommended W for a tank my size, but maybe it burnt out trying to maintain.

Just as the header says. Stopped working after a couple months. It’s the recommended W for a tank my size, but maybe it burnt out trying to maintain.


Rated 1 out of 5 stars
By Mike on Dec 27, 2022

Flooded with water within days.

Initially seem to function properly as the LED lit and it started to get warm so I inserted it into the tank, but checking on it a couple days later the temperature

Initially seem to function properly as the LED lit and it started to get warm so I inserted it into the tank, but checking on it a couple days later the temperature was same as room. Immediately noticed condensation around the label and when I removed the unit it was flooded with water. No visible signs of damage or obvious points where water may have entered.


Rated 1 out of 5 stars
By Prism on Apr 8, 2023

Broke almost immediately

This broke almost immediately, like a couple weeks into use. Would not recommend at all.

This broke almost immediately, like a couple weeks into use. Would not recommend at all.


Rated 1 out of 5 stars
By nanci on May 23, 2023

300 watt cascade heat aquarium heater

Won't buy again. Cord is too short. I do not recommend

Won't buy again. Cord is too short. I do not recommend


Rated 1 out of 5 stars
By Shelley on Nov 22, 2022

Fire hazard-melted my aquarium plants

I use this in my turtles tank for about two months. It melted plastic aquarium plants in my tank. When I tried to remove it, it burnt my hand. I would not recommend

I use this in my turtles tank for about two months. It melted plastic aquarium plants in my tank. When I tried to remove it, it burnt my hand. I would not recommend this product as I think it might be a fire hazard.