How on Earth do you guys manage to keep humidity up?

[Adalrich]

First of all, hi to everyone, as of yesterday, I'm a proud owner of a small (about 3 cm long) bracypelma smithi.

I thought it'd be relatively smooth sailing, but I've run into some unexpected problems with humidity, or rather, how to keep it from falling below 50 %. From all the source material I read and videos I watched, I thought that I'd only need to add water about once a week to keep the humidity at a comfortable level. (What exactly this level is, is another problem - more on that later.)

So I put her small plastic container inside my 30 cm x 30 cm x 30 cm Exoterra (I don't want to disturb her by taking her out of her old home just yet, as she molted just before I bought her. I'm anxiously waiting until I can get my hands on that molt Plus, she might be just a tad too small for a terrarium that big) so I could easily monitor the temperature & humidity levels.

I then poured some water in one of the corners, in the same way one would overflow a water bowl, and thought I'd be set for a while. The humidity rose from 40-45 % to around 65. I checked back a couple of hours later and was rather surprised to see that the humidity had sunk to about 51. I decided to just wait on it, and checked back again some time later to see that it was below 50. I added some more water, the humidity level rose back to the 60-65 range and then went to sleep. I checked the meter in the morning and- it was at 51.

I became seriously puzzled at this point. Why does the humidity level fall that fast? I don't think I should be pouring water in to the terrarium every couple hours, isn't wet peat (I'm using unfertilised peat bought from a pet shop, it should be perfect) just an open invitation for mould? It is winter here in Finland, though, and the air inside is rather dry- when I unpacked my thermo-hygrometer and tested it, it showed that the humidity in the room was about 31 %. Plus, I've heard that Exoterras tend to be a little too well ventilated, and I've already covered half of the mesh roof to keep the humidity in.

What on Earth should I do? Just keep adding water? Cover the rest of the roof? Is there something wrong with my meter? Am I slowly turning my spider tank into a mould culture?

I'd also like to ask you this: What exactly IS the right level of humidity for a brachypelma smithi? There's been a ridiculous amount of variation in the caresheets and recommendations I've read. So far, I've been told that:

~50 % is enough.
55-65%, MUST NOT LET IT FALL BELOW 50!!!
65-75 %.
75-90 %. (!!!)

From what I gather, 55-65 is the most reasonable one, and most sources seem to agree on this. Is this too wet/dry for my spider? Am I panicking for nothing? Please correct me if I'm wrong, I don't want to kill little Hildegard

 

[jallen]

The larger the tank the harder it is to keep humidity up during winter. I would suggest putting the spider in a clear bowl a few inches in diameter with a small amount of holes or ventilation. There is a fine line on too much ventilation and not enough. Little ventilation and high humidity will lead to mold especially from leftover food from the spider. high ventilation and low humidity will leave your spider vulnerable to bad molts and possibly death. I see nothing wrong with 50% humidity for that species as long as water is available for drinking by misting once a day or every couple days. You never mentioned what your using for heat ( maybe you did ) but adding heat can raise the humidity when the soil is wet and has heat to it. As I stated earlier it would be a lot easier for you to downsize the cage for a little while. My spiderlings are all kept in clear bowls or jars according to their size, some substrate misting, and a heating pad can keep moisture droplets on the side for a couple days where i mist. Havent had any problems with this setup yet. My humidity depending on how much or often i mist can be 80% down to 40% Internal hydration is important so keep it fed up and misted and you should be fine.

 

[Bongo Fury]

http://www.petzoo.co.uk/product_info.php?products_id=41
^This is WAY too big for your small smithi. This is how I keep mine:
Small plastic food type container
Dry substrate
Water dish (shallow and no wider than legspan)
I'll overflow the dish a little, especially during premolt. That's about it, enjoy

ETA: I don't think that enclosure is appropriate for a terrestrial of any size, it has too much "headroom". It looks perfect for Avics though, with a little modification.

 

[CuddlesTheTarantula]

Maintaining humidity

What are you using to cover the wire mesh?

I have hermit crabs that have to be kept at high humidity levels and I put clear plastic wrap under the top of the tank lid, leaving only about 1/4 of it open to the air. I've also used a damp but not dripping small towel/wash cloth in the past and draped it over the top of the tank.

As for humidity levels for a B. smithi, I'd say 60-65 percent would be fine.

 

[Adalrich]

You never mentioned what your using for heat ( maybe you did )

Sorry about that, I didn't realise to mention heat since there are no problems with it (at the moment ). I don't have any form of special heating in my tank, since the room temperature's warm enough. (21-23 C, or 69-73 F)

^This is WAY too big for your small smithi. This is how I keep mine:

Yeah, I know, I rushed with the tank. I bought it before I settled on a sling, I was looking for a juvenile spider first. I suppose I'll detach the thermo-hygrometer and look for a suitable plastic box, add some holes for ventilation and furnish it. I've still got cork bark, peat et cetera left.

What are you using to cover the wire mesh?

I measured the roof and cut a piece from the cardboard box the terrarium came in. I suppose it's not the best insulator

I guess swapping for a smaller enclosure should solve my problem for the time being, but what should I do if this happens the next winter, or the winter after that? Just keep watering?

 

[CuddlesTheTarantula]

If I were you I'd definitely try to use some clear plastic wrap to cover the roof.

 

[Adalrich]

If I were you I'd definitely try to use some clear plastic wrap to cover the roof.

Yeah, that's a really good idea, I should have some in the kitchen.

Edit: I've taped some plastic wrap on top of the tank, it covers about 55 % of the roof. Let's see how it keeps the humidity in.

I found a clear, plastic 17 cm x 17 cm x 11 cm candy box. Compared to her current box, it's a mansion Is it still too big, or should I just start making some ventilation holes and dig out the peat?

 

[Newflvr]

Smithi baby

I have several of this species and they are not kept in tropical conditions. Mine are 2" to Adult I keep them on Vermiculite/peat mix, with a water dish in corner. R/H is around 35%-40%, if ready to molt I mist 1 end of the enclosure to increase humidity.My temps vary from 72-76F. I hope this helps some. Kevin

 

[Exo]

I keep slings in deli cups with some holes drilled in the lid and moist substrate, that keeps them plenty humid. For my larger juveniles and adults I use plastic wrap on the lid and dry substrate.

 

[dopamine]

Aren't smithis a desert dwelling species? 50-55% humidity should be enough, right?

 

[Adalrich]

Aren't smithis a desert dwelling species? 50-55% humidity should be enough, right?

Well... This is exactly what I was talking about. No offense to anyone who's posted, in fact, I'm very grateful for all the advice you've given, I didn't expect my topic to generate so much interest so fast, but there's no clear consensus on humidity. The recommendations are all over the place.

Wikipedia has this to say:

"The natural scrub-forest habitat is complex, where shading retains moderate humidity (around 55-65%). Many older books are in error in saying they are from desert/arid habitats."

And:

"For years these spiders were mislabeled as being a desert species, resulting in the deaths of many spiders from inadequate humidity. It is best to maintain a range of temperature and humidity in the tank, with an area where the spider can rest in moderate 55% humidity (and ideally the burrow and the water-dish here), and a drier area of substrate over a heat source. The average enclosure humidity should never fall below 40 percent."

http://en.wikipedia.org/wiki/Brachypelma_smithi

Then again, the article could've been written by anyone.

The plastic wrap seems to have helped, the humidity is now 63 %.

 

[Exo]

Aren't smithis a desert dwelling species? 50-55% humidity should be enough, right?

Actually, in their native habitat they inhabit both coastal forest and rocky desert. They also live in burrows in the wild, which are much more humid that the surface is. I do think that 55% humidity should be enough though.

 

[Exo]

Well... This is exactly what I was talking about. No offense to anyone who's posted, in fact, I'm very grateful for all the advice you've given, I didn't expect my topic to generate so much interest so fast, but there's no clear consensus on humidity. The recommendations are all over the place.

The plastic wrap seems to have helped, the humidity is now 63 %.

I keep my 3in female at about 65% and she does well, so you should be good to go.

 

[mitchnast]

ultrasonic humidifier inside mass enclosure.
like this

thats the way I do it anyway.

 

[Adalrich]

I keep my 3in female at about 65% and she does well, so you should be good to go.

Let's hope it stays where it is now. That leaves only one problem: the size of the enclosure. I don't think I should let her into the Exoterra yet; she's too small. I think I'll start working on that candy box...

 

[nakazanie]

Don't worry about it. Just keep water there. She'll be fine.

Nak

 

[Adalrich]

Don't worry about it. Just keep water there. She'll be fine.

Nak

I admit it's tempting to open the lid of her container and let her walk out into the terrarium and see what she thinks of it. I'm just afraid she'll climb too high, fall, and - SPLAT.

 

[Steve Calceatum]

TBH, my B. smithi does perfectly in a DRY cage.....in fact, she prefers it. Any moisture on the sub sends her climbing walls. Based on my experience in this hobby, Wikipedia has as much substantially accurate information on Theraphosid husbandry as your LPS.......I'll trust the hobbyists, and the webpages directly related to tarantula care, and their natural history.


As for humidity, restricting ventilation is a good start. Room temp should be about 75 - 80 degees. Use two water dishes, and soak the substrate a couple times a week. This keeps my 10-gallon Avic avic enclosure sitting at about 90% humidity....and her ventilation is not as restricted as I've seen on other Avic setups.

However, I do admonish you to reconsider your attention to the Rh in an enclosure that is not care-specific related. Brachys are battletanks, and can take a bit of environmental punishment. 50%Rh is not that much more than standard room Rh (depending on your individual environment). My room is at 40% Rh, and I were to put a hygro in one of my arid setups with a freshly-filled waterdish, it would most likely read 50%-60% Rh. My non-Avic / Emp tropical setups get one waterdish, and a weekly substrate soak. They ride at about 75% Rh on average.....for these setups, I rotate a hygro through all of them periodically for spot-checks.

 

[codykrr]

i will never understand why people fret over humidity so much.............:wall::wall::wall:

just put her on dry sub with a water dish a little smaller than her leg span and she will be fine.

seriously there are only a handful of species i will even make sure there moist at all times.
T. blondi, M. robustum and my H. incei(but not too moist for them)

like said above, if i kept my B. smithi on moist or even damp sub she climbs the wall till its dry. even after a watering she climbs the walls. she likes it bone dry, with just a water dish.

the only time i even overflow her water dish is right before a molt. and thats easy enough to tell when its going to happen.

there kinda like that infomercial "set it and forget it"

 

[Adalrich]

TBH, my B. smithi does perfectly in a DRY cage.....in fact, she prefers it. Any moisture on the sub sends her climbing walls. Based on my experience in this hobby, Wikipedia has as much substantially accurate information on Theraphosid husbandry as your LPS.......I'll trust the hobbyists, and the webpages directly related to tarantula care, and their natural history.

I know Wikipedia isn't exactly an authority on tarantula-keeping, but I've read similar reports from different websites, and well, I just dug up the Wikipedia article since it's easier to find than some random articles/posts at random websites. I did notice, though that the article does not list ANY sources. Like I said; it could've been written by anyone.

By the way, I'd like to trust the hobbyists as well, but as you can see even by glancing at the responses to this thread, everyone seems to have different opinions.

I'm guessing that part of the problem is that tarantulas are tough enough to withstand humidity/temperature that isn't exactly like their native climate, and when one dies, it's hard to tell whether it was from old age, stress, some sort of disease, internal damage, mites, mould, chemicals or because the temperature/humidity level was off by 5 degrees. People seem to have success even with wildly varying setups.