Recommended Posts

Hello everyone,

I need to buy 2 hygrometers for my terraria.

There are plenty around, from very cheap to reeeeeeeeeally expensive. But the issue is that most of them are designed to measure the humidity in houses/appartments, which is far from what we expect in our terraria (hopefully, otherwise you either have issue in your house or in your growing set-up!)

So, do you recommend any model that is precise at high humidity levels?



Link to post
Share on other sites

Hello Vincent, hygrometers measure the humidity from 0 to 100%, I have seen no hygrometers that measure different moisture.

We growers do not need professional hygrometers, most of us, use digital hygrometers low cost found in any oriental shop, supermarket or electronics stores.

I use a digital thermometer/hygrometers with probe, paid 8 euro.


Link to post
Share on other sites

I just use a cheap non-digital one from ebay that is built in to the thermometer. You can see it as the smaller dial here

Link to post
Share on other sites

I have some experience on different hygrometers. Some time ago I used Lucky Reptile Hygrometer Deluxe Pro meters (,2$pid2,3335$pid3,7773728/products.html). I still have one in another terrarium.

For my main terrarium I have Lucky Reptile Humidity Control Pro 2 which is a controller but has hygrometer too.

And finally I recently bought an analog humidity gauge (Lucky Reptile precision hygrometer).

The problem is the very high humidity of terrariums. Usually, when humidity increases above say 80 %, hygrometers start to display an offset to the real humidity. For example when comparing the controller's humidity value to my reference meter (accurate) the difference is +12 % to +20 %, eg. when the controller displays 95 % the real humidity is around 75 % - 83 % and so on. At the same time the analog gauge shows between 75 % and 80 % humidity. So what is real?

To sum it up: almost every (cheap) meter shows too much or too little at the top of the scale. Also the humidity displayed depends on the atmospheric pressure. Luckily most CPs don't require a precise humidity as long as it's high.

I'm still in progress to compare different meters to my reference meter (non-commercial self-made) so I currently don't have a good recommendation. Basicly the meters sold for terrariums SHOULD be ok. Good luck.

Link to post
Share on other sites

Thanks for the answers.

I fully agree with pmatil: even though they are all supposed to measure up to 100%, the range at which they are precise usually does not reach more than about 80%. See an example here in the product description:

The measuring range for humidity: 0% to 100%

But the humidity accuracy is ± 5% (40% ~ 80% of)

The main issue is: how to check if they are precise or not!

Link to post
Share on other sites

I bought one of these >

I placed it on my bathroom windowsill where my Neps reside. I became curious of how accurate it was was after reading that they can be +/- 5% inaccurate.

Soon after, i ordered a second one for another windowsill when my Nep collection started expanding rapidly. But first of all, i placed it side by side with my first (identical) hygrometer in the bathroom while i was waiting for a nice hot bath to run one evening. They displayed a difference of 4 degrees C between them, and a difference of 6% RH constantly. Combine this with the +/- 5% inaccuracy and they become practically worthless, especially where the forthcoming winter night time temps could mean life or death for some of my Neps :sad:

I'll avoid the cheap ones in future !

Edited by Welshy
Link to post
Share on other sites


Actually, I've heard that the inacuracy can reach much more than 5%. In reality, it seems it's more something like 10-15% at high humidity!

I've ordered 2 different ones and I'll let you know after I can perform some tests.

Link to post
Share on other sites

Yes, 10-15 % error is correct. For my humidity controller (lucky reptile) the inaccuracy is specified as +/- 5 % BUT the sensor element inside has specs of at least +/-7 % at high humidity and I've measured an error of about 10-15 %. So I have to adjust the humidity 10-15 % higher so that the real humidity is correct. Very annoying.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.