Heater vs ac..

[ArnoldosAquariums]

Excuse the mess but here is my dilemma and I need as many opinions as possible.

I have just installed a mini split and it’s literally on the opposite side of the aquarium so the air goes towards the aquarium the entire time.

My wife runs it around 72° and the tank keeps going down to 75… Even though the Finnex heater is set to 80.

Now it’s not that I want to be 80° but the Finnex is really off so for me to get 77 I had to keep it at 80. For me to raise it up I now have it at 83° and it seems that it thinks that at 82° it has reached the temperature and shuts off even though three thermometers are showing around 75 to 77°.

So I’m thinking maybe the heater is bad?

I also thought about moving the tank because I don’t want that heater running all the time either and I’m curious if the AC is going to make things worse.

I totally understand I have to drain the tank. I’m actually thinking about buying a new stand for it as well.

The question is is there a possibility to just drain it so there’s only a third of the water left and then move it? The reason is there’s an engineer goby and a few nems in there. I really don’t want to have to pull everything out move it in buckets and put everything back in.

Now the mini split is also about 15 feet away from the tank… So I’m not sure if that is what’s causing all these issues or if it’s just a crap heater.

I know the first step should be to just buy a new heater and see what happens… But I wanted to get everybody’s input. 

 

[Suohhen]

Heaters are notorious for being horribly calibrated. The ehiem heaters have an adjustment to dial in calibration and I've had some that even when I adjust the calibration all the way it can go it still wasn't enough. So basically you have to keep adjusting it until you reach your desired temp regardless of what the dial says. That is to say don't crank it and leave it but find the setting where it turns off at your desired setting.

 

[ArnoldosAquariums]

Heaters are notorious for being horribly calibrated. The ehiem heaters have an adjustment to dial in calibration and I've had some that even when I adjust the calibration all the way it can go it still wasn't enough. So basically you have to keep adjusting it until you reach your desired temp regardless of what the dial says. That is to say don't crank it and leave it but find the setting where it turns off at your desired setting.

i did, but it seems to be up and down. I turned off the mini split air conditioner for a bit and a shot back up to 79… My fear is maybe this heater isn’t keeping up with the air conditioner. It’s a 40 gallon system and it’s the Finnex 200W heater (The one without a separate probe)

 

[elysics]

Dropping in a second heater, at least during the summer, might be worth a try

 

[ArnoldosAquariums]

Dropping in a second heater, at least during the summer, might be worth a try

Can’t hurt. Still thinking that means the first heater may be going bad…?
Reading the reviews on the HMO 200 seems to confirm this is garbage.

 

[Bad Company]

That's a pretty small tank, a 100W heater ought to be able to keep it at least 20° F warmer than the ambient temperature.

 

[Lost in the Sauce]

Sounds like a combination issue of too much cooling and a heater that needs upgraded. First thing I would do is check the heater calibration, second install a glass or some other solid lid covering much of but not all of the top. That screen top isn't helping it hold in heat with the mini split above it.

Yes it's possible to drain almost everything and move the tank. Maybe leave 2 inches of water. I would take all rock out. Even with nems on it. You don't want any of that shifting while you move it.

 

[ArnoldosAquariums]

Sounds like a combination issue of too much cooling and a heater that needs upgraded. First thing I would do is check the heater calibration, second install a glass or some other solid lid covering much of but not all of the top. That screen top isn't helping it hold in heat with the mini split above it.

Yes it's possible to drain almost everything and move the tank. Maybe leave 2 inches of water. I would take all rock out. Even with nems on it. You don't want any of that shifting while you move it.

Thanks! Split isn’t above it per se.. it’s the opposite wall… but totally get it.

 

[Lost in the Sauce]

Thanks! Split isn’t above it per se.. it’s the opposite wall… but totally get it.

Being on the same wall would be a blessing. Being out in front of the cool airflow is part of the issue. All of my mini splits are mounted high So there's a good six to eight feet in front of them of normal air until you get into the cool stream. If your blower is blowing straight out toward the wall where your tank sits, The cold air is probably hitting that wall and diffusing in every direction including straight down onto the open top water. Water transferred heat to air, drops water temp.

Essentially you've got a cold (dry) air-fed evaporative cooling system going on.

 

[Cell]

I have to oversize my heaters in the basement tanks to offset the colder air.

 

[Pico bam]

Surprised no ones mentioned a heater controller. These are generally used with heaters that don't have a internal thermostat. But can be used just fine with a heater that has one as long as you turn the heater up higher than the temperature needed. Then the heater controller turns the heater on and off. People will often turn the heater up all the way and just let the controller turn the heater on and off and this will keep the heat set accurately.

 

[Celestion]

Useing the ac to control tank temp is not good theory..if I leave for the day, the house is 88 at night on arrival the thank temp is 80 , think swamp cooler it's always going to run under the room temps right.. exposeing rapidly moving water to the room air cools it right...in winter the room is 70 degrees , the tank heater runs almost continuesly to maintain 78...

 

[ArnoldosAquariums]

Useing the ac to control tank temp is not good theory..if I leave for the day, the house is 88 at night on arrival the thank temp is 80 , think swamp cooler it's always going to run under the room temps right.. exposeing rapidly moving water to the room air cools it right...in winter the room is 70 degrees , the tank heater runs almost continuesly to maintain 78...

i’m not using to control tank temperature. That’s not even remotely close to what’s happening

 

[ArnoldosAquariums]

Being on the same wall would be a blessing. Being out in front of the cool airflow is part of the issue. All of my mini splits are mounted high So there's a good six to eight feet in front of them of normal air until you get into the cool stream. If your blower is blowing straight out toward the wall where your tank sits, The cold air is probably hitting that wall and diffusing in every direction including straight down onto the open top water. Water transferred heat to air, drops water temp.

Essentially you've got a cold (dry) air-fed evaporative cooling system going on.

Seems the issue is that the Finnex is an unstable piece of crap. My LFS had one last Aquatop but it was a 500W. It was insanely overkill, but may be just the ticket. It’s been stable since without much electricity being used.

 

[Lost in the Sauce]

Heaters fail for sure but that's a lot of watts you just threw in there. If you're going to use that 500 are you going to put it on a controller?.

Not if but when that heater also fails (they do, part of it), if the contact points fail together in the on position, a 500 watt heater will fry that tank in quick work.

 

[ArnoldosAquariums]

Heaters fail for sure but that's a lot of watts you just threw in there. If you're going to use that 500 are you going to put it on a controller?.

Not if but when that heater also fails (they do, part of it), if the contact points fail together in the on position, a 500 watt heater will fry that tank in quick work.

A 500w heater will work faster than a 100w. It’ll use less in the long run.

Aquatop has a built in controller than hasn’t failed me in years BUT I have it on Apex for a failsafe.