Review on FEDOUR Submersible Aquarium Heater with Protective Cover, Adjustable Thermostat for 5-40 Gallon Fish and Turtle Tanks - Available in 30W, 50W, 60W, and 120W Options by Becky Evans

Rating: Great filter, I have (I think) a 20 gallon tank. not completely filled, but until full this heater keeps a good temperature. I have the air conditioning on and the fan running and it can get very cold in my room. Don't worry about my turtles. I've touched the water with my hand it's definitely not cold, just about the temp I set it to (warm), I don't have a thermometer or an accurate form of temperature measurement to see if it's the EXACT temp set, which I put on the filter, but keeps warm. While waiting for this filter the water was pretty cold, the air conditioner and fan didn't help but now I have peace of mind knowing I'm cold in my room but my turtles in the tank have tropical weather 😃 , it should be noted that I was looking for a heater and while most heaters are the same (maybe not the same, but at least they look the same) this one is good for turtles and similar animals because they can't break. Either to bite the glass, this filter is encased in a plastic container, so don't worry about your sea creature attacking the filter and then chewing on the glass, or getting electrocuted, or an end goal scenario, you'll be fine go, it's durable, there's a knob on the top that you turn to set the temperature you want, the temperature is shown by an internal thermometer that you can see from the outside. Pros: - works as advertised - dial to select temperature - visible thermometer - dark case, on any subject, deer doesn't particularly stand out, fits well (this pro is more of an opinion than a true pro feature I think) - turtle bites are safe (my turtles don't even bother, they ignore it 😁) - a long cord? (by visual estimation I think it's 4-5ft long) - not a big obstacle, shaped like a cylinder, like 3 whiteboard markers together with a rubber band 😃 Cons: none (for now, will update if I do)