HCA: Hermit Crab Association

I just bought Hermit crabs in Sept 2014 so still new to all of this. I live in Arizona and the weather just started to get hot fast. I noticed that the teperature in the crabitat is at a steady 90 ish. The Humidity fluxuates and I mist it twice daily. I am wondering how i can lower the temp without lowering the humidity. The humidity in a day ranges from 50 to 80, pending if i have just misted it or just came home from work. I have a small computer fan i sometimes use to give some air flow but then the humidity plummets. Any help would be appreciated.

My tank is a 50 Gallon fish tank and it has aproximatly 5 - 7 inches of a sand and eco earth mixture in the bottom. Glass sides and plexi glass lid with cut out corners (for air). I also today unplugged the tank heater thinking maybe that would help.

As of yesterday (i cleaned the tank for like 2 hours) i now have one crab who is almost completly out of his shell and is not moving so i would really like to get this solved. Yes i have moved him into the issolation tank and he still has his color. We are thinking he is getting ready to surface molt as he is a Jumbo crab.

I have the same problem in Socal; it is already in the 90's outside and we turn the AC up (warmer) in the day when we are away usually to 80 degrees. So, it would get too hot in the tat with the UTH on, edging to the 90's. I finally bit the bullet and bought a Zilla thermostat ($35 I think). That way when the tank gets over 85, the UTH is shut off-until it goes back down to 80 degrees, then it is turned back on. That way I can't forget if I turn the air down to 75 that I need to turn the heat UP in the tat.

So my humidity stays pretty constant; but if you are opening the lid to let the hot air out you will lose the humidity, too. We have very dry days like you, in the 10% humidity range and I need to keep the lid pretty well closed then.

What if you use an aquarium pump and stick the hose in the tank to circulate air? Just thinking...

°°°°°°°°°°°°°°°°°°°°°°°°°°°
Rainbow Dash - PP
Apple Jack - PP

So are they ok at that high temp?

Never thought of that Aquarium Pump Hose. Ill have to check it out

90 could be okay if they have cooler spots in the tank to move to. Have you moved your thermometer around in the tank to see if it's a steady 90 all throughout?

What's your heat source? An undertank heater? I would leave it unplugged and see if that helps. What's the temp in your house? Are they located near a window that could be letting in light and causing the tank to heat up?

If you want to increase airflow and not kill the humidity, the air hose is a good idea and you can use it to make a DIY humidifier to keep the humidity up. Instructions here: http://hermitcrabassociation.com/phpBB/ ... 39&t=26260

I would worry about a jumbo that's getting ready to surface molt. Is your substrate sandcastle consistency? A jumbo needs at least 10" of substrate to molt safely. If he's out of his shell pretty far and not moving, it could also be a sign of overheating.

– No I have not tried moving the Thermometor.

– I have a SMALL under tank heater that is in the middle on the back glass (not under the tank but on the side). My house varies last time I looked it was at 80. ( I live with my grandmother so it usually is whatever she wants and has it as, I have no control over it sadly). They are located in the front living room by the hallway and under a AC vent. The problem is my house has big windows in every room so sunlight is always there.

– It’s packed pretty tight but moveable and the others are digging and have molted recently in the same tank. (I cant figure out how to attatch a photo or I would)

- I also moved the jumbo and the issolation tank into my sisters room which is the darkest and coldest room in the house and no one goes in there. Hoping the isolation, darkness and coolness will help him.

This should help you post pictures.
http://hermitcrabassociation.com/phpBB/ ... =8&t=87783

I couldnt figure out the photos at the moment but i think i figured out the links so here goes nothing - - - - Sadly i report that the Jumbo Crab (Monster) has indeed died while i was at work today.


Issolation Tank

https://www.dropbox.com/sc/5fsxqp3js973 ... 3AGUPhxeKa

Main Tank

https://www.dropbox.com/sc/2479dcjffo1i ... hINvWRkWda

Your enclosure looks great.
I like that dish, it looks familiar,
Oh wait, I have two just like it.

Rose_v73 wrote:I just bought Hermit crabs in Sept 2014 so still new to all of this. I live in Arizona and the weather just started to get hot fast. I noticed that the teperature in the crabitat is at a steady 90 ish. The Humidity fluxuates and I mist it twice daily. I am wondering how i can lower the temp without lowering the humidity. The humidity in a day ranges from 50 to 80, pending if i have just misted it or just came home from work. I have a small computer fan i sometimes use to give some air flow but then the humidity plummets. Any help would be appreciated.

My tank is a 50 Gallon fish tank and it has aproximatly 5 - 7 inches of a sand and eco earth mixture in the bottom. Glass sides and plexi glass lid with cut out corners (for air). I also today unplugged the tank heater thinking maybe that would help.

Not using the under tank heater would be best, with it being so hot outside I doubt it'll get below 75°F even with a thermostat or A/C on. And wow! 50g and only 5-7"?? Fill that big bugger up! I believe what you have is a 19" tall 50g? If so 10-12" would fit nicely, it'll be great for your crabs, and still have 7-9" of room on the surface for decor.
Also, humidity at 50% isn't safe it'll be best at 75%+. I believe while letting through air flow at corners like you have already and adding a couple small moss pits or just one big one would boost it. But with 10% outside something bigger may be better like the humidifier. But tbh why not both? Moss is great for hermits to cuddle in and eat while keeping their gills misty and a humidifier keeping the moss pit wet would be super convenient (I'm sure some maintenance from you would be necessary at SOME point though).


Mommy of 10 PP babies:
Poseidon (Sid), Toby, Matty, Junior, Aries, Kaylee, Turbo, Adrian, Pepper and Flower. RIP Octavius & Fred

Indeed the tank I have is 19 tall x 13 wide x 48 long. Now I only have 4 crabs but until I get everything in order and am more comfortable with everything I won't be buying more. I hear 4 is plenty.

I also do have a whole box of New Zealand Sphagnum Moss in the tank. I try to have one side like beach style and the other jungle llike.

I also do two levels sometimes in the tank to mix it up.

I'm so sorry you lost your big guy. If you think it could be something other than temp/humidity, we can help if you answer the questions on the Help Template in the Emergency section.

Humidity levels are usually the inverse of the temperature - so if you lower the temp the humidity will go up, and if you make it warmer using a UTH or heat lamp, the humidity will go down.

Your problem will be the fact you live in a very dry climate, so the air in your home is sucking the moisture out of tank. You can combat that either by sealing the tank up (not ideal, since the crabs do need fresh air) or by continually adding in moisture to replace what was lost. A humidifier would work really well for that, especially with how big of tank you have. I personally recommended a modified room humidifier, since they last longer and create more humidity. There are photos a bit down the page here of a Crane humidifier, which a lot of crabbers are using since it's easy to convert: http://hermitcrabassociation.com/phpBB/ ... er#p935973

90 is an okay temperature so long as there are cooler areas for them to retreat to. The top of my tank stays around 90-95, but it's closer to room temperature (70) at the bottom, so the crabs can go wherever they feel most comfortable. Some like it cooler, and others stay out in the open in the blistering heat all the time. 80-85 degrees is where the majority of PPs like to be, which is why we suggest aiming for it. Moving the thermometer around the tank will give you a better idea of what the situation is like. And with UTHs, you can buy a $10 plug-in lamp dimmer at the hardware store, and dial the heat back as much as you need it so its not too hot or too cold. It doesn't have to be all or nothing!

Well I put a second thermometer on the (jungle side) of the tank a few days ago. And closed up two of the four holes I have.

The Desert side stayed steady at 90 degrees and humidity has been around 80-90 (if recently misted. The Jungle side is staying at just under 80 degrees and around 50-60 humidity. I think from what is being said that this isn’t a bad thing. I also did buy the suggested aquarium air pump and will put that in tonight to hopefully circulate the air. Also bought one for the humidity & an air stone as well. I am thinking of getting a reptile waterfall for the tank. I am afraid if I put a bowl of water and the air stone in it they may drown, some of the air stones are big/tall. I also like the idea of a decoration waterfall and the bubbles and stuff I think may help both of my problems. What do you think of that idea??

I am going to add this to here about Monster as well since I have already spoke about him. I also did start a thread about him in another category. I will post the link below. Apparently the day before monster dies my grandma said she noticed tan spots on his body (he was a bright red crab). Any ideas on the spots??

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