In line Heater

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Aquarium Advice Addict
Dec 5, 2004
Glen Ellyn, IL
I just put in an in-line heater, ETH 300w. seems to be working great. Anyone else try these?
Interesting. Can you give more info on the product and the size of your tank. Do inline heaters need to be higher wattage overall as opposed to the standard type of heater.
Heater is an In-line Hydor ETH (eth=external tank heater?). It is a bit bulkier than a normal heater. Main advantage is that it is outside if the tank in line with a canister filter or pump, out of site. The water flows through the heater, and heated water is pumped into the tank, so it circulates well. The heater must be verticle, so no air gets trapped. Fits 5/8" hose. If you dont have a sump to place a regular submersible heater in, this heater seems to do a good job and keeps the display tank from getting crowded with devices. Link is below. So far I am satisfied with mine. I believe the wattage recomendations are the same for submersibles. I am using a 300W on a 55 gal tank. Smaller ones are available.

Ok thanks. I didnt know if you needed a higher wattage heater due to the increased water flow around the unit or not.
I had/have one. Use to use it with my 29 gallon SW. Worked very well. Temprature was always constant, and TomK2 is right, one less thing in the tank!
Has anyone used one of these heaters with a FilStar canister filter? I am looking at getting the FilStar XP 2 and I want to make sure that the ETH 201 heater (5/8") fits the tubing.
Just an observation, and a shameless review plug at the same time, but perhaps one of you could upload this product, and the others could review it.

(please don't let me jack this thread and forget I was here)
I'd say for the minute difference in cost, go ahead and get the 300w. It will do the job just fine, but it will also be useful should you ever wish to use it on a larger tank.
I don't think that you can overstress the heater. If they fail, I beleive it is the switch that gives out. Thus, a lower power heater that does not cycle on and off as frequently might have more life to it???? But, I don't know if that is enough theoretical benefit to outweigh the ability to upgrade to a larger tank that zac already brought up with the larger heater.
I also oversized for possible expansion. I have a 50 gallon, and I use the 300w ETh inline with an XP3. This time of year (since I haven't started up the furnace yet) mornings in the house are in the low 60's. My tank is constantly at 78.
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