Using two heaters vs one

[ud56]

Anyone have advice on using two vs one heater. I know about the redundancy thing,I’m not asking about that. I’m wondering about the efficiency. Let’s say I need a 200w heater. Would one be more effective in keeping up my temp. As apposed to two individual ones struggling because they are not powerful enough on their own to heat the tank.

 

[Gumbies R Us]

What is the size of your tank?

 

[ud56]

What is the size of your tank?

25g lagoon. But the room it’s in gets to about 62 in the winter months

 

[Gumbies R Us]

With a tank that size, you really only need one heater. I have a 20-gallon tank in a house we keep at 65-69 degrees, and I only have one heater in my tank. My tank would stay around 78-80 degrees year-round.

 

[ud56]

With a tank that size, you really only need one heater. I have a 20-gallon tank in a house we keep at 65-69 degrees, and I only have one heater in my tank. My tank would stay around 78-80 degrees year-round.

I prefer one heater but I can’t find one big enough(wattage wise) that fits. What brand and wattage do you have?

 

[Gumbies R Us]

I prefer one heater but I can’t find one big enough(wattage wise) that fits. What brand and wattage do you have?

(might be wrong since it was so long ago) I think I use a Fluval M 100w heater

 

[MnFish1]

Anyone have advice on using two vs one heater. I know about the redundancy thing,I’m not asking about that. I’m wondering about the efficiency. Let’s say I need a 200w heater. Would one be more effective in keeping up my temp. As apposed to two individual ones struggling because they are not powerful enough on their own to heat the tank.

It's not efficient to have 2 heaters set at the same temperature - as they will 'compete' - If you feel you need 2x200 watts buy a 400 watt heater. If you want 'the redundancy thing' - 2 heaters is fine.

 

[MnFish1]

I prefer one heater but I can’t find one big enough(wattage wise) that fits. What brand and wattage do you have?

There are heaters up to 1000 watts - how many watts do you need? If I'm understanding you have a 25 Gallon heater - and at times the room temperature is 62 or so?

 

[Randy Holmes-Farley Verified Community Expert]

I typically used a bunch of heaters for my system in the past.

Current plan is one 500 w in spring/summer/fall, and an added 800 w in winter. Both are titanium types.

Each are controlled by two inkbirds (one plugged into the other), making it impossible to overheat from a single controller failure.

 

[BryanM]

Anyone have advice on using two vs one heater. I know about the redundancy thing,I’m not asking about that. I’m wondering about the efficiency. Let’s say I need a 200w heater. Would one be more effective in keeping up my temp. As apposed to two individual ones struggling because they are not powerful enough on their own to heat the tank.

I'm not sure about two heaters in a tank that small unless you had a sump.

But the thought process (in my mind) for two heaters is that either one can keep the tank at the proper temp. You don't undersize them, because if one dies your tank will get cold.

I use separate helios controllers for each, and neptune programming to only use one at a time.

 

[ColorMeGone]

I run 2, 50 watt heaters hooked to an Ink Bird. 1 is all I need but if one craps out then the other will take over. I check them both once a month to make sure all is well. I have new spares on the shelf if needed.

 

[MnFish1]

I typically used a bunch of heaters for my system in the past.

Current plan is one 500 w in spring/summer/fall, and an added 800 w in winter. Both are titanium types.

Each are controlled by two inkbirds (one plugged into the other), making it impossible to overheat from a single controller failure.

I'm curious - do you set them for the same temperature? or do you set one lower?

 

[Hishman]

Each are controlled by two inkbirds (one plugged into the other), making it impossible to overheat from a single controller failure.

Can you explain this more? I’ve always used an external controller like apex to turn off the power to the Temp controller. Dual controllers plugged into each tower sounds a lot simpler and frees up space on the apex.

 

[ud56]

There are heaters up to 1000 watts - how many watts do you need? If I'm understanding you have a 25 Gallon heater - and at times the room temperature is 62 or so?

I was thinking one 200w because I was afraid anything smaller couldn’t hold temp but I couldn’t find any that would fit so I’m thinking of one 150w to see how it does

 

[Randy Holmes-Farley Verified Community Expert]

I'm curious - do you set them for the same temperature? or do you set one lower?

When I use both they will be set to the same temp, though they will be a little different since the temp sensors read slightly different. In the scenario where I’ll use two, one is not meeting the demand, and the INKBIRD controllers have a 1 deg F gap between on and off so they will not be fast switching.

 

[Harpo]

I have 4 heaters: 1 in my display, two in my sump and one in my frag Tank.

 

[Besieged]

I keep my house at a solid 68F year-round. In all my freshwater tanks, "properly" rated heaters struggle to maintain temps. Despite being overrated for the tank size, the one on my 20g long pea puffer tank simply cannot seem to get it above 75ºF... I probably should have returned it, I guess.

I didn't want that problem with my 50+14 gallon reef system. I also worry about a heater getting stuck on and cooking my entire system, ESPECIALLY since I would need a single heater rated for 300watts to ensure I can overcome interior temps.

Therefore I elected for a pair of 150w heaters, both set to ~82ºF. That way, a single failure in one (especially if I weren't using an Apex) shouldn't result in drastic overheating.

No, running two is not going to make it any more - or any less - efficient, generally speaking. Heaters are already pretty efficient, with sufficient surface area for their output, and the wattage used is the wattage used. You will, however, reduce wear and tear - such as it is - by doubling the heater count, since they spread the load and individually don't have to work as hard, as long, to achieve and maintain desired temps.

I have my two on opposite sides of the pump section of my AIO, and controlled by my Apex, with a 1ºF delta set. It takes them about 90m to warm from 77.9º to 79.1º, and then it takes the system about 70 minutes to lose that heat... but in the process, the heaters get to spend that 70m in an off state, instead of constantly switching off and on, off and on, trying to keep it exactly at the set point.

Not to mention the temp probe in my Apex is far more accurate and reliable than the thermostats in any heater I've ever owned to date.

 

[Jamie814]

Each are controlled by two inkbirds (one plugged into the other), making it impossible to overheat from a single controller failure.

If I'm understanding you correctly, the 2nd inkbird is plugged into the first one? If the first inkbird fails in the off position or reads temp higher than it is it will shut all heat off to the tank. It protects from overhearing but not underheating.

I've always recommended 2 smaller heaters, each controlled separately over one large one.
This gives you protections from over or under heating your tank.

 

[MnFish1]

When I use both they will be set to the same temp, though they will be a little different since the temp sensors read slightly different. In the scenario where I’ll use two, one is not meeting the demand, and the INKBIRD controllers have a 1 deg F gap between on and off so they will not be fast switching.

Thanks - that was the question!

 

[RocketEngineer]

Anyone have advice on using two vs one heater. I know about the redundancy thing,I’m not asking about that. I’m wondering about the efficiency. Let’s say I need a 200w heater. Would one be more effective in keeping up my temp. As apposed to two individual ones struggling because they are not powerful enough on their own to heat the tank.

If the two add up to 200W they won’t struggle because you have the same energy input. Watts are watts. Heaters are 100% efficient because we measure efficiency as how much work gets done vs energy converted to heat.

I personally go for two heaters at 75% of what I need. One heater is set slightly lower than the other. This way, one heater does most of the work and the other can cover the cold nights. Being only 75% of the rating, if it gets stuck on, it is a slower rise. As a backup I have an independent controller that shuts them both off if the tank gets too warm. The cheap heaters do their own switching so they break before my expensive power strip.