Best aquarium heater for your fish tank 2017 , check out this heater on amazon here is a few links for different sizes on amazon.
Eheim Jager 25W: https://www.amazon.com/gp/product/B00425AXQA/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&tag=unconvention-20&camp=1789&creative=9325&linkCode=as2&creativeASIN=B00425AXQA&linkId=de8e3decd5fe4bb3c56ddeb33496375e
(affiliate)
Eheim Jager 100W: https://www.amazon.com/gp/product/B003SNU1I2/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&tag=unconvention-20&camp=1789&creative=9325&linkCode=as2&creativeASIN=B003SNU1I2&linkId=60727c8dcc2dcac37f6eef99dca0ccf2
(affiliate)
Eheim Jager 300W: https://www.amazon.com/gp/product/B003I5UC0W/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&tag=unconvention-20&camp=1789&creative=9325&linkCode=as2&creativeASIN=B003I5UC0W&linkId=aa745dbc29138097de767e38e2612776
(affiliate)
Price: $17.99
Orlushy Submersible Aquarium Heater 150W for Marine Reef Fish Tank Sump
Product Features: 1. 110V-120V/60HZ 6-foot power cord, 2. Fully submersible. 3. Universal heater for marine, freshwater or tropical aquariums 4.automatic safety shut-off feature, and overheating protection. Available In: Length - 9" 15-30 Gal... (as of February 13, 2020 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)
Price:
Hygger 500W Digital Quartz Aquarium Heater for Fresh-Water and Salt-Water, with External IC Thermostat Controller and Thermometer, Fast Heating Submersible Thermostat for Fish Tank 60-120 Gallon
(74) 
Price: $13.99
Mylivell Aquarium Heater Submersible Fish Tank Water Heater Thermostat-100W
Product Features: Reliable circuit and high material ensure output of the heat and keep the water temperature inside the tank steady Temperature indicating scale can be adjusted between 20°~34°C(68°F - 93°F). Totally submersible Durable and ... (as of February 18, 2020 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)
Price: $26.99
Had an Aqueon pro kill 10 fish on me . So went back to Ehiem. Never had a problem as well.
Ehiem rocks!!
I agree with u the best heater 90% of my tanks have them
i started going heater less cheaper still informative video
Great review, Eheim makes top quality products
I agreed with you in the heater. I have one in my 90G that has still going strong for 3 years. As the other heater I have start to go, I will be replacing them with Eheims. Thanks for sharing.
Just a little advice, move your bottom sucktion holder up the heater and off the element :).
I’m an Eheim girl!! ♥♥
This heater regarding safety feature is good but to calibrate it is another story which is extremely complicated task this heater gives random temperature