Tunnels and Moisture
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Tunnels and Moisture
I have heard that if your crabs tunnel, the tunnels can hold moisture and start to grow mold. I know I should replace the substrate three times a year and should scoop out old food and poop at least once a week.
I just want to prevent mold in the tunnels. I don't want to collapse them because one of my crabs loves tunneling and he may be in one somewhere.
My humidity is currently at 70% on one side and 80% on the other. Temperature is between 75 and 80 degrees Fahrenheit. The substrate is a mix of play sand and eco earth and it is between 5 to 6 inches deep.
I don't see any signs of mold currently, but I would rather take steps to prevent it than to fix it when it's too late.
I just want to prevent mold in the tunnels. I don't want to collapse them because one of my crabs loves tunneling and he may be in one somewhere.
My humidity is currently at 70% on one side and 80% on the other. Temperature is between 75 and 80 degrees Fahrenheit. The substrate is a mix of play sand and eco earth and it is between 5 to 6 inches deep.
I don't see any signs of mold currently, but I would rather take steps to prevent it than to fix it when it's too late.
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Re: Tunnels and Moisture
Hello!
I have never heard of that. I also have never replaced my substrate. I do sometimes work new substrate in, but that is once a year.
I personally have my humidity up to 99%. My temperature ranges from 79 (low at night) to 85 (hight during the day).
Mold doesn't hurt the crabs. It can harm us if we breath it in.

I personally have my humidity up to 99%. My temperature ranges from 79 (low at night) to 85 (hight during the day).
Mold doesn't hurt the crabs. It can harm us if we breath it in.

Truly blessed to have incredible creatures, wonderful friends and my amazing family in my life!! I'm very thankful & grateful for all of them! www.thehealthyhermit.com
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Re: Tunnels and Moisture
I’ve let my substrate sit for years without any problems. I’ve only ever had mold in the tunnels once, after a poor crab died and decomposed down there.
With multiple hermit crabs having different molting cycles, remixing or replacing substrate is rarely a practical option for me.
Mold won’t be an issue. Just spot clean the surface when needed.
With multiple hermit crabs having different molting cycles, remixing or replacing substrate is rarely a practical option for me.
Mold won’t be an issue. Just spot clean the surface when needed.
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Re: Tunnels and Moisture
I have had my crabs for 7 1/2 years, and have never replaced the substrate, just added new and mixed it in.
"If there are no dogs in Heaven, then when I die I want to go where they went." -Will Rogers
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Topic author - Posts: 10
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Re: Tunnels and Moisture
Thanks, everyone! You've all been super helpful 

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Re: Tunnels and Moisture
I have had my tank set up for over two years, and transitioning sizes with the same substrate, without any issues. You don’t need to remove substatte very often, just scrape the top layer for poop and leftover food.
Crabber Since 2016
7 Caribbeans & 2 Ecuadorians
I am the proud owner of my hermit crabs, aquarium fish, and isopod totes!
7 Caribbeans & 2 Ecuadorians
I am the proud owner of my hermit crabs, aquarium fish, and isopod totes!
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Re: Tunnels and Moisture
What new substrate do you add mines is sand and the coconut stuff ... for humidity ... can I just mix in more of both when ever .....
And the smell of the cage like gets strong cause of the humidity is that normal and probably healthy !!?
Cause it is so humid or whatever
And the smell of the cage like gets strong cause of the humidity is that normal and probably healthy !!?
Cause it is so humid or whatever
Re: Tunnels and Moisture
Most people use a 5:1 ratio of sand and eco earth. If you don't have crabs down you can add sub freely, if you have some down you can safely add up to an inch a day, just don't pack it down.