FlytrapCare Carnivorous Plant Forums

Hello people,

I’m new to this site and new to carnivorous plant terrariums. I’m setting a 4 foot long, 2 foot high old aquarium for my Heliamphora. I’m in the super early stages, I only have my lights, tank, and false bottom(still need to fix that) and my plants(which are doing well outside for now). My house stays around 73F all the time and my tank is going in a corner with no sunlight. The humidity in the spot where the terrarium is going is 40% currently if that helps.

I’ve been reading countless forums and websites on how to cool a highland terrarium. Everything on each one is pretty confusing because everything contradicts itself like fans, peltier coolers, modified ac units, chillers, etc. If anyone has any tips for me on how to cool my terrarium, PLEASE HELP ME!! I was originally going to use a two fanned peltier cooler, but I learned it wouldn’t cool my tank enough with a 10 degree drop for my Heliamphoras.

I’m planning on keeping the humidity at 90% with either a repti fogger on or a ultrasonic fogger(which one is best?). My lights still need to be fixed on top of the terrarium too.

So really, my questions are:

1.) How should I cool a 4ft long terrarium? (My original version was 2, two fanned peltier cooler as well as a small computer fan.

2.) Best devices for humidity? (I was going to use an ultrasonic fogger at first but I don’t know the basics to it)

3.) What should I use for as a lid or should I not even get one?

4.) And finally any links or useful/ successful products would be a big help for me

Sorry for the longish post, but if you read it all, thank you so much in advance, any tips and trick will be well appreciated!!!

1. The peltier coolers are the only thing I know of to cool a terrarium (other than building a terrarium out of a small freezer). Obviously blowing in external air you have to run a fogger 24/7 with a peltier on the terrarium. The peltiers are also very loud when running, like a small airplane taking off in your house (at least the one I bought off eBay).

2. The reptifoggers are ok but for my next terrarium I'm using an AirInnovations humidifier with a plastic tube attachment. It's much more durable, holds a gallon of water, and will pump out a huge amount of fog - your terrarium can be completely white and opaque if it's set to the highest setting.

3. I would get a lid. It helps maintain the humidity. Plus with a lid you don't need to run the humidifier non-stop. I have mine running only half of the time each hour.

You could of course also build a chest freezer or mini-fridge terrarium with a thermostat to prevent it getting too cold if you want.

I just have mine in the basement under LED lights so they cycle from 75*F down to 70*F with no input on my end for cooling. I've found that the ones I have don't really need it any lower...they may appreciate it and grow faster, but my "trophies" aka H. sarracenioides are growing very well so I probably won't bother changing my set up until I decide to upgrade the terrarium to a larger size. The peltier I have now is just a back-up I use in the middle of summer if the basement isn't cooling down much.

Thanks for responding so quickly! Usually on the salamander fourms I’m on, no one responds till the next few days.

Anyways, I have two open spaces on top of my terrarium because a plastic bar splits the tank in half for some reason, I know I’m either getting a glass or a polycarbonate lid cut to fit. Should I get just two panels to fit on top? Or should I get a partial screen on one side for air flow?

Also, how may peltier coolers do you recommend to cool my tank? I’ve seen some online and people were hoping they could hopefully cool their 2 foot terrariums for orchids. I’ve also seen people on some other not as well known saying their peltier cooler kept their tanks around 40F!

As for the humidifier, I’m going to check into what you’re using instead of a reptifogger (I called one of my local pet stores and they told me repti foggers broke on them after a few when they used it for 24/7 because being on for long shortened the life span of it)

Depends on how much the peltier cooling units vary and which one you're getting, or if you'll be assembling this DIY... But to cool a 4 foot terrarium you definitely will need more than one. From what I can tell based on the cooling peltier panels I have bought, I would say about 1 per 10 gallons.

With my current 30 gallon terrarium and one peltier panel (with two heat sinks+ fans, and one cooling fan) it drops the terrarium only 10 degrees under room temp (which is good enough, I don't think it's an absolute necessity to be growing Heli's in ultra highland conditions like in the 50's or 40's).

I personally would get two panels for the lids since I never bothered with air flow on my Heli's fearing a drop in humidity. If you will be using a peltier cooler you will have enough in-flowing dry air that I would just get the double sealed top.
But... some screen on top may not be the end of the world, you would just have to run the fogger more frequently (or even 24/7) to keep the humidity from dropping. I hate refilling the water reservoir in my foggers since I used distilled water to both prevent mineral build up on the plants and from busting the ultrasonic component, which is why mine are in a sealed box full of condensation that will buffer the humidity when my fogger is off half the time. The dynamics of the terrarium will be affected with an open side, maybe in a more positive way...with a more closed system you will get water pooling in the bottom of the terrarium. I have at least 6 inches of clearance in mine (pots all stand on a platform) and I have to dump out about 4 gallons of condensed water from the terrarium every few weeks (which i don't mind since it acts as a humidity buffer and I also will make use out of it in the next terrarium rebuild, probably just having the incoming air flowing through a pipe and down over the surface to increase the incoming air's RH.). My Heli's are pretty much at 95%+ humidity all the time. You could probably safely drop the humidity down to 85-80% RH and still be ok depending on what species you are growing. I imagine with a half open top and a peltier running you will get more evaporation and may not need to worry about any pooling of the water.

The specific humidifier I have is an AirInnovations model MH-408

The tank is 55 gallons and I was researching peltiers last night, they were around $30+, a 2 cooling-fanned peltier was about $65 for one. Just a bit pricy. Do you think a combination of 2 largish computer fans and 2, two fanned peltier coolers would be equivalent or would help cool the tank down combined with a humidifier or fogger? Or should I go with a lot of fans w/ 2 polycarbonate lids and one 2, two cooling fanned peltier cooler?

Also, what do you think about an ultrasonic fogger in a open container (or just at the bottom),inside the terrarium to help with the humidity?

One more thing, with your humidifier, how did you place it inside your terrarium? Is it outside the terrarium with some sort of tube running into the terrarium or is it directly inside?

And because I have a false bottom that is 1 1/2 inches high, should I increase the height by 4 1/2 inches or more?

Thanks for your help!