Heat the tank, or the room?

[AfaceInTheCrowd]

I’m in the planning stages of a 500 gallon (120”x36”x30”).
It will sit in (what was my) dining room, behind a false wall. The room is 13ftx15ft, and has a single door access point, and one window.
The room will also have 2/3 large coral tables (maybe 72”x36”x12”). Mixing station barrels etc..
I’m wondering about whether heating, and cooling would be cheaper/more efficient if I maintained the ambient room temperature at 26.C,
I have gas radiator in there (could put on a separate thermostat to the rest of the house) and maybe buy an air conditioner to cool the room to 26.C during the summer months (although in UK so not many days are over 26 anyway )

**Looking for thoughts/ideas ✌

Thinking I could save on 2000+w of electric heaters as they would only “supplement” the heating of the tanks, and a portable air conditioner is around £300/$400..whereas a huge chiller is £2500/$3500

Thanks in advance

 

[Conovan]

over the long term the cost of energy would probably be less to heat/cool the room than the tanks. once that volume of water is at the right temp it will help stabalize the temp of the room.

 

[Jon Fishman]

Once pumps and lights are factored in, if you’re comfortable with what the ambient room temp would need to be, I would say that is the better way to go.

 

[BackToTheReef]

I'm considering one of these for heating/cooling a large tank:

Air Cooled Heat Pumps

Aqua Logic® Delta Star® Air Cooled Heat Pumps automatically handle both heating and cooling duties in fresh and saltwater applications.

pentairaes.com

 

[Dr. Jim]

I had an almost identical situation: 500 gal built in wall, but the room behind the tank was smaller than yours, about 8' x 14'. I had an air conditioner in that room which definitely helped, and, in fact, was enough to prevent needing a chiller. Much of the time, however, the door was open so air circulated into the adjacent sun room which was also air conditioned.

As far as heat is concerned, I would definitely say that heating the room with your gas heater would be more economical, but I would have back-up heaters in the tanks.

You might find a compromise between heating the room AND heating the tanks with tank-heaters so you can keep the room air at a more comfortable temperature for yourself.

 

[Dr. Jim]

I'm considering one of these for heating/cooling a large tank:

Air Cooled Heat Pumps

Aqua Logic® Delta Star® Air Cooled Heat Pumps automatically handle both heating and cooling duties in fresh and saltwater applications.

pentairaes.com

That looks like a good idea. (I'm looking ahead to my next build).
Do you know how to size the units to number of gallons?

 

[BackToTheReef]

That looks like a good idea. (I'm looking ahead to my next build).
Do you know how to size the units to number of gallons?

I do not, I have just started researching them. Since I am going to live in a cold climate I thought this might be a good option. HPs can be dang efficient. Expensive up front but operating cost is going to be lower and catastrophic failure seems much less likely.

There is another option for warmer climates: https://www.aquacal.com/heat-pumps/

They specifically list aquarium applications, need to confirm the titanium heat exchanger is salt safe but I think the minimum operating temp is in the 40s based on the info I have found so the temp range is definitely not the hyper heat Air Source Heat Pumps and Ductless Heat Pumps I am used to.

 

[AfaceInTheCrowd]

Thank you for replies, seems this may be the wa6 to go.

I would still have heaters in the tanks and that’s a valid point about pumps etc adding heat, so maybe the room might need to be 24.C but would have to experiment.

I am also concerned about humidity and a fresh air extraction fan (one in, one out) bringing in cold air, meaning the radiator would be constantly ‘fighting’ the fan.. it’s cold for like 5 months of the year here

 

[ichthyogeek]

I think you also have to contend with how insulated the room is, as well as how willing you are to working in hot temperatures. With a large tank, it's probably cheaper to heat the room, like everybody's saying.

As for humidity and fresh air extraction, take examples from the fish! Tuna and sharks regulate their body temperatures by having rete mirabila. Depending on how you plumb everything, you could run the hot air tubes around the cool air pipes or something similar (idk, I'm not well versed in gas exchange stuff for architecture).