Fluval P25 Submersible Aquarium Heater

This is a nice little heater for a small tank. I have a 2.6 gallon tank, and this heater fits perfectly in one of the filtering chambers. Its a fixed temp (non-adjustable), but seems to work great.

I bought this heater because of the Fluval name. It is supposed to be preset to 76-78 degrees. It is actually set to 82 which is too warm for my tank.

I purchased this heater for a 5 gallon betta tank. The heater is set to the temperature they need. It’s a no hassle addition to my tank. Just check the tank’s temperature now and the .

Good heater, and done a good job keeping the water temp consistent. But I frequently have to put it back on the side of the tank. The suction cups don't hold as well as I would like. But over all works well for its intended purpose of heating the tank

This has been keeping my 2.5 gallon beta tank about 76-77.5 deg depending on my house temp cycling with the pellet stove. The beta fish seems happier and it's working much better than the old 10 watt always on heater I had.

Plug it in and forget about it. Using it in a Fluval Spec V tank. Fits great in the water pump chamber.

I got my aquarium about 15years ago, my first original fluval heater lasted about 10 years till stopped working, so i ordered new fluval heater (exactly the same) lasted 3 years and one day just exploded in the water killing all my fish , black smoke everywhere - it was BAD. Thankfully i was home.

Works perfect for my five gallon. Perfect temperature. No complaints. Will update later if it ever fails or malfunctions.

I bought the Fluval P25 submersible heater to keep my betta warm. After just 6 months of use, the heater cracked underwater and sadly electrocuted my betta to death. When I inspected the heater, I found visible cracks in the plastic. I’ve attached images showing the damage. After this incident, I researched online and found multiple reports on Reddit and aquarium forums like Reef2Reef from other users who had similar dangerous experiences with this heater. I can’t post links here, but you can search “fluval p25 heater cracked” on Google and see for yourself. This is unacceptable for any aquarium product, especially when it risks the lives of our pets. Please be cautious and consider safer alternatives.

I don't know about its durability and how reliable this product is, but so far so good. It does what's supposed to do and it takes very little space in my 20l tank. Just plug it in and let it do its job.

Excelente producto

Fluval is supposed to be a good company but I can't keep my Aquarium Temperature bove 24 degrees. The Fluval Aquarium Heater is covered by plastic. Hence it keeps switching off after every few seconds. It is therefore unable to adequately heat the 10 gallon tank. I am disappointed at the poor design and inadequate heating. 😔

It was too much for my 5 gallon tank. I have another 25W heater that keeps my Betta tank at a perfect 79° but this one kept it at 82-83° which is on the warm side for a Betta. I like the neat appearance but I don't understand why it kept my tank too warm when it's the same wattage as my other heater. So a very nice product but I couldn't use it. Disappointing. I still give it 4 stars because in another tank I'm sure it would be great.