Dual Heater Setup Question

[14Discus]

Ok.......now I have it all set up to prevent both too high and too low temps for my Discus tanks......even if I’m not home.

2 regular heaters powered by controller to 87 degrees.......if overheated, will stop heating at 90 degrees as per controller
1 heater powered by reg outlet to 84 degrees.......if controller w 2 heaters fails, this one will turn on at 83 degrees and is, until then, basically sitting idle until water should get too cool.
Note.....we do have a whole house generator, so if power goes out.....power will still be given to all units involved.

One additional thought abt heaters......I purposely put all heaters in the tank as opposed to my sump. Why u might wonder. If the pump bringing water into the sump should fail with the heaters in the sump, the tank will get too cool as the heaters would heat the water stuck in the sump and not the fish tank. If the pump bringing water to the sump fails with heaters being in the tank, the heaters will continue to heat the tank as desired. I was going to put the heaters in the sumps when I installed them, but got to thinking abt this scenario and decided not to.

[Oxboy]

Ok.......now I have it all set up to prevent both too high and too low temps for my Discus tanks......even if I’m not home.

2 regular heaters powered by controller to 87 degrees.......if overheated, will stop heating at 90 degrees as per controller
1 heater powered by reg outlet to 84 degrees.......if controller w 2 heaters fails, this one will turn on at 83 degrees and is, until then, basically sitting idle until water should get too cool.
Note.....we do have a whole house generator, so if power goes out.....power will still be given to all units involved.

One additional thought abt heaters......I purposely put all heaters in the tank as opposed to my sump. Why u might wonder. If the pump bringing water into the sump should fail with the heaters in the sump, the tank will get too cool as the heaters would heat the water stuck in the sump and not the fish tank. If the pump bringing water to the sump fails with heaters being in the tank, the heaters will continue to heat the tank as desired. I was going to put the heaters in the sumps when I installed them, but got to thinking abt this scenario and decided not to.

Bill, don't you think you could get away with just one main heater instead of two? It's only a 60 gal.

[14Discus]

I’ve always used two primary heaters....both working together less than one unit working more. Also, if one goes down, the other can pick up the slack. Pairs are used for both the 60g and the 75g tanks. Just my thoughts. You can elect to do as you wish. I’ve always been a “plan for the worst” and hope for the best kinda guy.

[Acerrato]

Hi Everyone! This thread has been very helpful and a bit confusing as well - I was hoping someone could clarify! I currently have 2 300W Eheim heaters in my 125g. Both heaters are hooked up to the Bulk Reef Supply heater controller. My internal heaters are set to 86F - the heater controller reads: PV 86F, SV 87F. I'd like to use this heater controller as an "insurance policy" as you guys suggested above. I guess I was confused about what the heater controller was. I thought that my controller was actually heating my tank - it is not, correct? This means that if my tank gets to 87F, my heaters will get cut off? I thought the SV was the temp that my tank tries to heat to.... Clarification would be appreciated! Should I change my SV to 90F?

[14Discus]

I’m not sure exactly what PV and SV means as mine is a different brand. That being said, I would leave my heaters set to 86 plugged into the controller and set the controller temp to 89 or 90. Then....the controller would be on merely providing power to the heaters unless the heaters went crazy and heated the tank to 89 or 90 at which time the controller would cut power to the heaters. You would then see the higher temp and know your heaters malfunctioned. While it’s tempting to set the controller to 87, my thinking is that it’s too close to your heater desired temp of 86.....going a few degrees gives water fluctuations a chance prior to cutting power needlessly. Btw....in being concerned about controller or main heater failure, plop another heater in plugged into the wall separate from the controller and set it to 84 or 83. Since your water would be at 86, this third heater would be alive, but inactive ( not heating) until your tank dropped below the 84. That way you have protected your tank for too high and too low a water temp. Hope this helps.

[Acerrato]

Thank you Bill - PV is Process value and SV is Setting value. So the PV is currently at 86 and the PV set at 87 - I will be adjusting now - thanks again!

[dagray]

I have two 300 watt heaters in my 75 gallon. This keeps temps very even. It also allows the tank to stay around 83 degrees while the house A/C is turned down to 65

[Oxboy]

I have two 300 watt heaters in my 75 gallon. This keeps temps very even. It also allows the tank to stay around 83 degrees while the house A/C is turned down to 65

Whoa..do you live in Death Valley?? 65 is icy.

Better hope one of those 300s doesn't stick on or you'll be having fishwiches for dinner.

[dagray]

Whoa..do you live in Death Valley?? 65 is icy.

Better hope one of those 300s doesn't stick on or you'll be having fishwiches for dinner.

Oregon Desert. Tank is by the dining room window. I use the Fluval E300 heaters and have had no problems in the years I have been doing this.

Last night temperature was below freezing by a couple degrees outside, and it will be in the mid 60s outside today.

[GabrielleSimpsonC]

I also use two heaters at once, but one almost never works. Basically, he is there as a spare ..

[Willie]

There may be a misunderstanding here.

A 2-heater set up is recommended so that if one heater gets stuck, nothing bad will happen to the fish. The idea is that neither one is powerful enough to overheat the tank on its own. If one gets stuck on, the other one shuts off, so only one heater is doing the damage. Putting 2 X 300 W heaters into a tank defeats the purpose of the set up, since either heater can cook the fish if it gets stuck.

In most situations, 2 X 150 W heaters is usually more than enough for a 75-gallon, or even 125-gallon, tank. When both heaters are working, there's more than enough wattage to maintain the tank in the mid-80's. If one gets stuck, a 150 W heater will likely not cook the tank. If one fails, the temperature will gradually drop into the mid-70's. Leaving the discus in the mid-70's overnight, or even 24 hours, is unlikely to do any harm. (BTW, it's always a good idea to keep a new heater in storage in case an existing one dies.)

Hope that's clear, Willie

[dornblaser]

I will be the outlier here, I prefer to have both heaters be able to support the desired heat in the tank individually if needed. I have two 300 watt heaters along with two filters in my 75g. Having two heaters that independently control temperature at either side of the aquarium makes sense if you accept that your tank water is not at a uniform temperature.

[Vinni Smith]

Happy Birthday to meeeee........
Happy Birthday to meeeee........

Nancy gave me my earlier B-Day present today.
800 Watt Hygger auto heater!!!
I LOVE these things.
I have the 500 Watt in the house on the main 112 tank.
I had 3 heaters in the shop 112 and could barely keep it at 86 because we keep that place so cool for the employees.
This 800 Watt should do the trick EASY PEASY.

They have auto shut off for WCs, which I love.
And they are also supposed to have a safety shut-off for malfunction.

BTW, it may just be me being an idiot but all my fish 4" and under seem to do so much better at 88-90 F.

Vinni