Keeping substrate "sandcastle consistency" ?

stormypanda · Post by **stormypanda** » Sun Jun 11, 2017 7:16 am

Hi everyone! I recently adopted 4 hermit crabs after they were used in a classroom as part of a scientific experiment. They now live in a 29 gallon tank with about 6-8 inches of substrate (made up of 5 parts playsand to 1 part coconut fiber). When I first put the substrate into the tank, I had made sure that it was the correct consistency aka sandcastle consistency. I've kept the humidity in the tank between 75%-85% by misting and keeping a screen cover + saran wrap on top. It's been a few weeks now and I am curious whether or not the substrate will stay at sandcastle consistency for a long period of time? Two of the crabs have buried themselves in the substrate. I'm just a bit worried the substrate will harden up over time and they'll be stuck underground. Or does the substrate stay at the original consistency for a really long time?

I am very new to hermit crab care and would appreciate any advice. Thanks for reading

YouTube · Post by **GotButterflies** » Sun Jun 11, 2017 9:37 am

Hello! Welcome to the HCA!

Did you mix the substrate with dechlorinated marine saltwater or dechlorinated freshwater?

Recommended humidity is 80 and above. Hermit crabs have modified gills and need the humidity to breathe.

You can use a chopstick or a pencil, and go down the front of the crabitat where you know no crabs are. Stick it in slowly. If you are able to go all the way down and come back up and it doesn't cave- your substrate is fine.

Edit: do not dig crabs up. Also, spraying tank can lead to flooding, so please be cautious with that. Also, are you using dechlorinated fresh water to spray? Very important.

To boost humidity- glass tops- moss pits - air stones in their water bowls.

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stormypanda · Post by **stormypanda** » Sun Jun 11, 2017 10:06 am

GotButterflies wrote:Hello! Welcome to the HCA!

Did you mix the substrate with dechlorinated marine saltwater or dechlorinated freshwater?

Recommended humidity is 80 and above. Hermit crabs have modified gills and need the humidity to breathe.

You can use a chopstick or a pencil, and go down the front of the crabitat where you know no crabs are. Stick it in slowly. If you are able to go all the way down and come back up and it doesn't cave- your substrate is fine.

Edit: do not dig crabs up. Also, spraying tank can lead to flooding, so please be cautious with that. Also, are you using dechlorinated fresh water to spray? Very important.

To boost humidity- glass tops- moss pits - air stones in their water bowls.

Sent from my iPhone using Tapatalk

Hi, thanks for the warm welcome!

I mixed it with dechlorinated freshwater.

Okay I will do my best to keep the humidity above 80, generally it seems to be around 85%.

I tried the chopstick method and the sand formed a tunnel (chopstick-sized) once I pulled the chopstick back out. So I think it appears to be alright for now? Would spraying the walls of the tank rather than spraying the sand itself help out with decreasing the chance of flooding? I do use dechlorinated fresh water to spray.

Thanks for the tips ~ I will look into those humidity boost methods!

YouTube · Post by **GotButterflies** » Sun Jun 11, 2017 1:34 pm

Yw! Happy to help! What type of hygrometer do you have? I would calibrate it to make sure that it is accurate. Under forums- crabitat conditions. Sometimes just doing that you will find out your humidity is fine.

Spraying anywhere can lead to flooding. I personally don't recommend it. How many inches of substrate do you have?

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stormypanda · Post by **stormypanda** » Sun Jun 11, 2017 3:24 pm

GotButterflies wrote:Yw! Happy to help! What type of hygrometer do you have? I would calibrate it to make sure that it is accurate. Under forums- crabitat conditions. Sometimes just doing that you will find out your humidity is fine.

Spraying anywhere can lead to flooding. I personally don't recommend it. How many inches of substrate do you have?

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I use the AcuRite 00613 Indoor Humidity Monitor that I got off of Amazon. I calibrated it 2 days ago and it was off by 1% (1 percent too high).

Okay so should I avoid misting the enclosure? It's just that that's been my main method of keeping the tank humid for these past few weeks. I'll look to invest in some other methods. My substrate is 6 inches at the lowest and 9 inches on the higher end, I have it sloped slightly in the tank.

YouTube · Post by **GotButterflies** » Sun Jun 11, 2017 4:51 pm

stormypanda wrote:
GotButterflies wrote:Yw! Happy to help! What type of hygrometer do you have? I would calibrate it to make sure that it is accurate. Under forums- crabitat conditions. Sometimes just doing that you will find out your humidity is fine.

Spraying anywhere can lead to flooding. I personally don't recommend it. How many inches of substrate do you have?

Sent from my iPhone using Tapatalk
I use the AcuRite 00613 Indoor Humidity Monitor that I got off of Amazon. I calibrated it 2 days ago and it was off by 1% (1 percent too high).

Okay so should I avoid misting the enclosure? It's just that that's been my main method of keeping the tank humid for these past few weeks. I'll look to invest in some other methods. My substrate is 6 inches at the lowest and 9 inches on the higher end, I have it sloped slightly in the tank.

Great! I love that device!

Misting every once in a while is not to big of a deal, but every day can lead to issues.

Sometimes even just adding more substrate (up to 1" every 24 hours without packing it down) helps too. I have a lot of substrate in all of my tanks. It's just something I do. I think it's really important. Perhaps if you wanted, try adding just a layer (1-2 inches) of moistened eco earth - moistened with dechlorinated marine salt water. The crabs can mix it in themselves. I tend to use a little more eco earth than the 5:1 ratio. I personally feel crabs would go more inland to molt due to the tide coming in by the beach.
To each's own though. All three of my crabitats are mixed with dechlorinated marine salt water.

I do love glass lids - you cannot use heating lamps with them, which really is a good thing when you are trying to boost humidity. Heating lamps can make the water evaporate out of the air. Most crabbers use UTH (ultratherms) which are under the tank heaters. We don't use them under the tank though, we use them to heat the air, so they are placed on the back of the tank above the substrate.

www.reptilebasics.com or www.beanfarm.com

Airstones in the pools help too. Moss pits are on going maintenance (rewetting/cleaning/adding) that crabs LOVE

Hope that helps

Post by **wodesorel** » Sun Jun 11, 2017 9:49 pm

Generally the substrate will dry out from the top down so you'll know if it's not staying moist enough. The better sealed your tank is and the more humid it stays, the less water you'll have to add. My large tanks upstairs I haven't had to do a thing to since November, but my small tank in my bedroom I have to dump a glass of water on every few weeks or it dries out too much. I can tell it's time when the surface is like fresh powdered snow.

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Crabnado · Post by **Crabnado** » Sat Jun 17, 2017 2:14 pm

We have two pools of water at one end of the tank. The crabs splash so much (and steal the water for underground building projects) that the whole 1/3 of the tank has permanently damp sand. It's like what would be at the waterline of the ocean. The other 2/3 we've strewn moss, coconut dirt, and bark chips over. The tank is covered in glass except a 5x6 inch hole where the heat lamp shines down on the moss pit. We mist daily and the combination keeps our tank around 80 per cent humidity. We live in an area with about 5-10% humidity so this is definitely all the crabitat. The environment seems to keep the sand the right consistency, with the help of the crabs tunneling.

YouTube · Post by **GotButterflies** » Sat Jun 17, 2017 2:34 pm

Crabnado wrote:We have two pools of water at one end of the tank. The crabs splash so much (and steal the water for underground building projects) that the whole 1/3 of the tank has permanently damp sand. It's like what would be at the waterline of the ocean. The other 2/3 we've strewn moss, coconut dirt, and bark chips over. The tank is covered in glass except a 5x6 inch hole where the heat lamp shines down on the moss pit. We mist daily and the combination keeps our tank around 80 per cent humidity. We live in an area with about 5-10% humidity so this is definitely all the crabitat. The environment seems to keep the sand the right consistency, with the help of the crabs tunneling.

I would be concerned about that much water in my substrate. Are you sure you don't have a leak?

Also, I don't recommend misting the tank- it can lead to flooding.

Not trying to harp on you here at all, please don't take it that way, but I also don't recommend coconut bark. If a crab were to go shell less the bark could puncture their tender abdomen.

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Post by **wodesorel** » Mon Jun 19, 2017 2:56 pm

Waterline dampness at the ocean would be tapping with the palm of your hand and getting water to pool at the surface. That would be waaaay too wet. You want it where if you scratch at the sand it fluffs up and is light, but still holds it's shape without dripping if you take a handful and squeeze. It should be like that all the way to the bottom of the tank.

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HCA: Hermit Crab Association