The key word here is "reasonable" I would use my air conditioner, if you live in a warm climate this will be your best bet as any air cooling system (if they exist?) for terrariums are going to be quite pricey! I know the systems they sell for aquariums are outrageous in price! Just move your set up to a room that has the air on (at the temp your set up requires)at all times and you should be O.K. I know that some situations dont make it that easy, but, if you can, that would be a simple solution. =)

How big is the terrarium? I'm not coming up with anything small on the usual industrial supply places, but then I don't know how big your terraium is. If it is small (These guys sell peltiers up to 226 watts, which might do the trick. I would do a bit of research first. You will also need a DC supply to run them, as they are not AC devices. You may also need a heatsink on the hot side, I'm not sure.

-DH

why do you need a terrarium that cool?

My terrarium is 4'H x 4'L x 2'W. I use it for orchids, and some require cool winter temperatures to bloom. (I have posted on the Orchids forum already).

The coolers for aquariums only cool water, and they have to do allot of work too, I think you would be better off buying a small window unit air conditioner and Jerry rigghing it so that the Duct runs into the terrarium and is controlled by a thermostat inside of the terrarium.

Hi
Have you thought of coinciding the "cool" period with cool outdoor temps.?? During winter you could draw air from outside with some duct work.. May get too complicated if you have to heat.
The best I've ever seen was a modified glass door fridge
Thermostat kept temp at whatever and a light chamber was attached tio the top with circulation to keep the heat down.
Was expensive of course but it worked!!! lol
gary

What orchids are you growing? I think Gary's approach is the best, use the seasons to your advantage and utilize the naturally cool outside air during the winter months.

I assumed that he/she lives in the warmer climates due to the fact that he needs a way to cool his set up, but I would like to know if Im right or wrong about the climate? If Im right, you shouldnt have a problem setting the room to the right temp with your AC, if not, I would have to agree that Garys way would be the best. =)

No problem except the powerbill at the end of the month, dropping a whole room that is not designed to go down that far to 50 f for an extended period of time would not be cheap at all, also he might have to heat other terrariums then. If you look at the origional poster at this point it seems that they are in Zone 8a in eastern north Carolina, which means that they are near the ocean, which helps regulate the temperature, putting it outside in "winter" might work, but you might have to set up a heater to make sure it doesn't get to cool, if you fail to keep it down around 50 will there be damage to the plants, or just no blooms?

I appreciate the responses. I guess no one has any experience using a thermoelectric cooler, small swamp cooler, or mini air conditioner to cool a large terrarium. I think as a first try, I'll see if a cool-mist humidifier will work as a small swamp cooler. If that doesn't work, I'll try a thermoelectric element.

Thanks,

Hank Cochran

Cool! (punn intended) Let us know which one works best. =)

Even orchids liking cool temps in winter can adapt to higher than 50... 60 is usually quite acceptable I think, but A/C is not - it's really bad for plants and dries them right out.

So did it work? I really wanted a follow up since I'm working with the same problem with my N. villosa.