Heating Multiple Tanks with Waterproof Heat Cables?

[Arty Mars]

Hello Fish Fam! 
I was wondering if anyone has ever heard of using these self regulating heat cables submerged in fish tanks under gravel, in sumps or inline pipes etc.  They're often used in Reptile Enclosures, preventing frozen pipes, melting snow on rooftops and regulating soil temperature in gardens etc? I'm from Australia so never seen these before as we don't often have problems with snow or, just cold weather in general 🤣

I was thinking it could be possible to wire up lengths of these cables with thermostats for multiple fish tanks to increase the temperature slightly, most of them actually regulate their own temperate somewhat passively, as the temperature changes the electrical resistance adjusts to either shut them off or allow more or less heat to be created; however it's usually in the extreme ranges of 60°-120°C / 140°-250°F.

Not sure if these temperature cables exist in lower temperature sensitivities or safer DC 12Volt currents. Not even sure how *waterproof* they really are etc

So many variables to think about so thought it would be interesting to know if any other hobbyists have seen these used before in submerged applications. 

Edited November 4, 2021 by Arty Mars
Multiple typos and spellchecks because i'm an adhd mess and never proofread xD

[Zenzo]

I have heard of many people using heating pads that sit underneath their aquariums to raise temp. I have never heard of anyone attempting to submerge them. I would think that if you could engineer these to sit underneath your aquariums on a shelf (like in a shallow channel), it would safer than trying to bury them under gravel.

With that being said, I don't know how effective these would be vs just having aquarium heaters turned down to a comparable temp, or heating the room a few degrees.

[Wingman12r]

Inglorious Bettas setup heating tape under her jars.

Edited November 5, 2021 by Wingman12r

[RadMax8]

I was recently reading The Optimum Aquarium and on the topic of heaters the authors very much recommended using under-gravel heating cable, not unlike what you have shown. The theory being that warm water rises, so you create a current from bottom to top and back again, thus taking nutrients to the roots of plants easier. 

I would imagine that the heat cord you have shown would be waterproof, otherwise it would trip the breakers all the time. The key would be getting it in the proper length and pairing it with something like an Inkbird heater controller. 

[StevesFishTanks]

Interesting ideas. If putting under the tanks I would worry about the pressure of the tank rims creating hot spots on heating elements/wire.  Inside a tank is possible but using and hiding a long cord vs a heating element or traditional heater seems like more of a hassle.

I think heating the room controlled by a thermostat that references a tank temp would be the safest and easiest option. Then add in tank heaters if needed for "hot" tanks above the "room" temp tanks

[Torrey]

Once upon a time, a few decades ago in the hobby, submerged "aquarium heat cables" were encouraged in the back of UGF to help evenly heat the tank and contribute to warm water raising in the back, air lift tubes pushing the warm water forward, where it would slowly sink and be pulled down through the gravel/rocks to start the filtration journey again. 

I suspect that combined with a Pymeter or Inkbird controller, you could see some great results. 

[Arty Mars]

On 11/5/2021 at 2:12 PM, s1_ said:

"Interesting ideas. If putting under the tanks I would worry about the pressure of the tank rims creating hot spots on heating elements/wire." 
My thoughts exactly I also worry about the temperature itself getting so hot it damages the glass bottom over time or affects the silicone edges. 

 "Inside a tank is possible but using and hiding a long cord vs a heating element or traditional heater seems like more of a hassle." 

Yeah I already use matten filters at the back of my tanks so hiding a few coils behind the sponge in the back of the tank was where i was thinking the cables could be hidden from view xD

 

On 11/5/2021 at 1:05 PM, RadMax8 said:

"The theory being that warm water rises, so you create a current from bottom to top and back again, thus taking nutrients to the roots of plants easier."

Yes that's another thing i'm very interested in! I've seen videos from people with larger community tanks that implement a "Reverse Under Gravel System" where they pump a small flow of water underneath a really thick gravel substrate which constantly aerates the gravel and prevent's muck building up, I imagine current from heating would have a similar effect 😄

 

[Arty Mars]

On 11/5/2021 at 11:45 AM, Zenzo said:

"I would think that if you could engineer these to sit underneath your aquariums on a shelf (like in a shallow channel), it would safer than trying to bury them under gravel."

I've also seen some Betta Breeders who made 6 inch shallow trays of water on shelving for this exact reason, they could then sit dozens of betta tanks in the tray and heat them simultaneously without concern of mixing water between tanks to prevent disease etc.

"I don't know how effective these would be vs just having aquarium heaters turned down to a comparable temp, or heating the room a few degrees."

I agree but with how much it will cost to buy and replace 35+ heaters in my fishroom over time i'm willing to gamble on some alternative methods first haha xD I think if i could find reliable cheap thermostats on Aliexpress etc It might just work 😄

 

[Andy's Fish Den]

@Torreybeat me to it, that years ago, there was a heating cable sold for aquariums, I may actually still have one at home in one of my bins of old aquarium equipment. 

I have thought about using the heat pad type things that are sold in pet stores in the reptile section, they attach to or just sit under the aquarium, and you can buy online rolls of the stuff and make custom lengths. You would have to have some kind of temperature regulator, as the pads do have a thermostat built in, but it may be too hot for fish. This is what Inglorious Betta used in the video linked above. 

As for having hot spots where the tank sat on the cable, you would have to raise the tank up to create a place for the cord to go. I know the heat pads sold for reptiles come with four hard rubber "feet" to put on the corners of the tank so the tank sits up off whatever you have it on, to allow the cord a place to go as well as allow air circulation underneath, 

[Maggie]

I just sold my old house a couple months ago. There was this same type of heat tape on the clothes washer water lines, which had been hooked up in the unheated garage. I had to replace the heat tape because it appeared old and was very brittle, and the plastic had cracked, exposing the wire in a few spots. I'd caution against using heat tape inside an aquarium, especially if you cannot see or feel the degradation of plastic that may happen. Also many heat tapes have a sensor that turns off the heat at temps above about 50 degrees Fahrenheit.