Penn-Plax Cascade Heat Preset Submersible Aquarium Heater, 8-in, 100-watt

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$24.49 (-43%) Chewy Price
$42.99 List Price
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About This Item

Details

  • Designed to maintain tank temperature within 1 degree of accuracy.
  • Features both Fahrenheit and Celsius temperatures on an easy-to-read gauge.
  • 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.
  • Safe to use in both freshwater and saltwater tanks up to 40 gallons in size!

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

Can you use this for a 5 gallon tank?

Answer by Chewy • Mar 17, 2023
This heater is safe to use in both freshwater and saltwater tanks up to 40 gallons in size.

Can this be used in tank with painted turtle's

Answer by Chewy • Feb 09, 2022
This heater can be used in a painted turtle habitat. It is safe to use in both freshwater and saltwater tanks up to 40 gallons in size.
Reviews
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4.2
Rated 4.2 out of 5 stars
97 Ratings
Terms & Conditions

45 Customer Reviews

Rated 1 out of 5 stars
By Crystal on Dec 30, 2025

Unreliable

Ordered two of these at the same time. One completely quit working after four days. The other is still working (3 weeks now), but is 3-4 degrees too low.

Ordered two of these at the same time. One completely quit working after four days. The other is still working (3 weeks now), but is 3-4 degrees too low.

Rated 5 out of 5 stars
By Jeff on Dec 26, 2025

Easy setup

I like these now these days all u have to do is plug them in and forget about them.

I like these now these days all u have to do is plug them in and forget about them.

Rated 4 out of 5 stars
By mikel on Jan 11, 2026

Quality item

My fish like that it heats them up when it's cold

My fish like that it heats them up when it's cold

Rated 4 out of 5 stars
By Hannah on Dec 13, 2025

Good enough

I like that you can see what temp you actually set it on

I like that you can see what temp you actually set it on

Rated 1 out of 5 stars
By hanna on Jan 20, 2025

Already broken

The heater overall worked fine in the beginning. I got this heater on December 27, 2024, and today (January 20, 2025) I was looking at it and it has a few cracks

The heater overall worked fine in the beginning. I got this heater on December 27, 2024, and today (January 20, 2025) I was looking at it and it has a few cracks in the glass. This is very disappointing since the heater was working great and now theres a few cracks in the glass of the heater. In case anyone is wondering, I did not "rough house" this heater, I was gentle with it. Luckily, I am cycling my tank and haven't put any fish in it yet. It is just upsetting I wasted my money. Especially since it barely lasted a month and I didn't cause it to break, it just broke on its own and I must get a new heater.

Rated 1 out of 5 stars
By Andrea on May 12, 2025

Worked for 4 months

It works for four months and then stopped working out of the blue. I would not recommend wasting your money on it.

It works for four months and then stopped working out of the blue. I would not recommend wasting your money on it.

Rated 5 out of 5 stars
By gail on Nov 21, 2025

work perfectly.

price is good also

price is good also

Rated 1 out of 5 stars
By Mira on Jan 27, 2025

Low Quality

Bought 2 of these and they both quit working after a month and 6 weeks. They were finicky from the start, not reading temp properly and leaving the water too cold

Bought 2 of these and they both quit working after a month and 6 weeks. They were finicky from the start, not reading temp properly and leaving the water too cold. Now I'll be spending more money to replace them instead of just buying higher quality in the first place.

Rated 1 out of 5 stars
By MATTHEW on Jan 31, 2025

Failed

This was delivered to me on 1/22/25. It failed on 1/30/25. I threw away the box. So, I can't return it. I ended up going to a local pet store to get a replacement

This was delivered to me on 1/22/25. It failed on 1/30/25. I threw away the box. So, I can't return it. I ended up going to a local pet store to get a replacement aquarium heater. Don't throw away your box in case you have to return or replace it.

Rated 5 out of 5 stars
By Stephanie on Jan 13, 2025

Works great!

Took my 40 gallon tall tank from 64 degrees to 70 in just an hour. My fish is a lot more happy now! I love that even though it cones preset, you can manually adjust

Took my 40 gallon tall tank from 64 degrees to 70 in just an hour. My fish is a lot more happy now! I love that even though it cones preset, you can manually adjust the temp setting. As well as a red indicator light that let's you know when it's running. Highly recommend!