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Highland Nepenthes Cooling and Lighting Solution

Highland Nepenthes Cooling and Lighting Solution Needed

Hello all, my name is Caleb, and I am new here. This is my first post not under the welcome section. I have a highland tank. I am not at home now, but when I get home I'll post some pictures. I am right now getting 73 in the day and 66-67 at night for temps. Ideally I want to get to 55 at night. I believe 70-73 is fine for highlanders, but correct me if im wrong. Specifically I have N. 'Ventrata', which I am not worried about night temps for, but I do have N. Jamban and N. Spectabilis. Right now I am using a peltier cooler. My tank is 30"L x 12"W x 18"H. I have it hooked up to a humidifier that pipes in humidity via PVC that is on a controller. I have tested it and it can sustain over 95% humidity easy, but I have it set to keep it between 85-90% humidity.

I am going to get a new light. Any suggestions for that would be greatly appreciated. Right now I am getting about 275 footcandles/3,000 lux. I need about 900 footcandles/10,000 lux/125 par if im correct. Please let me know what you all know works, ive only grown outside of the ventrata realm for less than a year.

Here is my plan for the cooling. It is something I havent found anybody else do, but I think it will work. I am unable to do a window AC unit, anything that has to do with a refrigerator/freezer, or aquarium chiller. I want a solution that I can maintain without opening the tank, and that is inexpensive. Here is the plan. My tank has 2-3 inches of water on the bottom. The plants are held above the water level by aquarium divider and upsidedown pots. I will put a 5 gallon bucket beside the tank. I will put two shelves inside the bucket, the bottom one being the same aquarium divider. The top one being a thin slab of treated wood, with a 120 or 140mm computer fan forcing air downwards. At the bottom, I will put a spigot. More on why later. I will drill a hole for a pvc pipe about 1 inch from the bottom of both the tank and the bucket. I will run the pvc through the water in the bottom of the tank through to the other side, then make a turn upwards and continue until I clear the aquarium divider. I will drill two more holes about 1 inch from the top of both the tank and the bucket for 1 more return pvc at the top above where the fan is in the bucket. The bucket will be sealed with a lid. The fan will be controlled by a temperature controller at night. Ice will be put on top of the aquarium divider shelf in the bucket, which will chill the surrounding air. The fan blowing down will force that cold out the pvc at the bottom, through the water in the tank and into the air. Because the return is above the fan in the bucket, it will pull the cool air back across the terrarium, cooling it evenly. The spigot at the bottom of the bucket is simply to easily remove excess melted ice. Do you think this method would work? I would probably still use the peltier as well.

Thanks in advance!
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Welcome! I'm in no way an expert on either HL Neps or the specific mechanics/physics of cooling, but I've looked into common options for the latter a lot for other highland CP setups (since I currently live in a hot, humid armpit for most of the year). So I'll take a stab at this...

For the Neps you listed, I don't think you need to realistically get all the way down to 55F unless you're planninh on growing the ultra-HL species. I would think that jambam and spectabilis would probably appreciate night temps at least in the low to mid 60's if you can (the ventrata will be fine with just about anything). The actual Nep experts can correct me if I'm wrong here!

As for the cooling, I read all the time that peltier coolers are just not super efficient so I'm not surprised you aren't seeing much of a temp drop right now. I'm having a hard time visualizing what your proposed set up will be though it seems like the basic idea is ice cools air in bucket-->fan blows cold air into tank water-->cool water lowers tank temps? Again, not a physics expert, but I have some doubts that 1) the ice will consistently cool the air in the bucket (seems like you'll either need a lot of ice, or be replacing it often) and 2) air from the bucket will consistently cool the water compared to just cooling the air around the plants instead. I'm not sure that heat transfer works well in your favor.

A related option is that some people can get away with using a DIY evap cooler in a bucket. But in that case you're leveraging the cooling effect of evaporation to cool the air pushed into the setup, and the drop you get really depends on the temp/humidity of the source air. Some people supplement with ice to get it down even cooler (still the similar issue of how long that ice is effective). I have also seen setups using water at the bottom of the tank where that water itself is cooled externally and circulated around the bottom of a tank. But those require some lines and pumps to circulate and usually uses an aquarium chiller or a refrigerant system to more efficiently cool of the water. Perhaps not an option in your circumstances since you already have the tank, but some people just opt for chest freezers or wine coolers set to turn on with temperature controllers. Other things like ventilation and lighting can be tricky, but the basic cooling method is taken care of.

Curious to see what others say though!
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I’m a new grower, been growing just over 2 years.

I grow a few HLs. Jamban among them. Mine are growing in intermediate conditions with high humidity,

My jamban pitchers consistently. So it seems happy. I’m growing Macrophylla, hamata, flava, argentii, etc ( argentii is new)

Mine are all young plants. A couple sulked over the summer, but now they are all pitchering well

Indoor small greenhouses, cheap LED panels, several Neps ,over 60 I think


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[MENTION=12888]Coursair[/MENTION] Not looking too shabby! What is the temperature in there? I'm guessing it stays at least somewhat cool since you have sphagnum growing pretty well. Also looks like there is condensation forming on the plastic.
[MENTION=12888]Coursair[/MENTION] Not looking too shabby! What is the temperature in there? I'm guessing it stays at least somewhat cool since you have sphagnum growing pretty well. Also looks like there is condensation forming on the plastic.

Greenhouse number 2 runs cooler

GH#1 runs warmer

Yes, high humidity [emoji274]

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What sensors/app are you using? I just set up a terrarium GH using an exoterra and would like to get remote readings of RH and temp too

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So basically going down to only 66 every night will be enough?
What sensors/app are you using? I just set up a terrarium GH using an exoterra and would like to get remote readings of RH and temp too

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Inkbird Wireless Bluetooth Thermometer & Hygrometer Smart Sensor Data Logger with Waterproof External Probe/Magnet/Alert for Android&IOS Used for Food https://www.amazon.com/dp/B0774BGBHS/ref=cm_sw_r_cp_apip_TjZRT1AyxENzm

It uses Bluetooth so I can’t get readings away from home, but The app works fine when I am home [emoji1360]