We've had three hermit crabs for a year now and none of them have molted yet. During the summer, we relocate them to another house with a smaller aquarium (10 gallon vs 20 gallon). Generally, our crabs appear to be happy and active at night, and they seem to eat well most of the time. I have two questions:
1. SUBSTRATE: In our 20 gallon aquarium, I think I have something between coconut soil and coconut husk. I really like it because unlike the coconut soil, the pieces are somewhat larger (but smaller than husks) and the water bowls are less dirty looking in the morning after a night of play. In our 10 gallon aquarium we have coconut soil, which basically looks like dirt. The crabs are covered in the dirt and the extra shells/water bowls/sponges get filled with it daily.
QUESTION: Do I need to replace the somewhat more fine coconut husk substrate with coconut soil in our main aquarium?
2. MOLTING: I read in one of the forums that the crabs need to build "caves" in the substrate in order to molt. While our crabs bury themselves every day and we do see evidence of tunnels, I don't really think they could build a cave in our main (20 gallon) aquarium with the looser coconut husk fiber.
QUESTION: Do you think our substrate is the reason our crabs haven't molted in one year?
SUBQUESTION: Back in April one of our crab's body/legs seemed to turn all white. We really thought that meant it was getting ready to molt, but it never did. Lately, it's gotten most of its color back.
Would really appreciate any guidance on these related topics. Starting to get worried we are not providing the optimal environment to encourage molting. Also worried that they may start molting this summer and we need to transport them back to our main home over Labor Day. Yikes!
Substrate / molting question - relatively new owner
-
GotButterflies
- Administrator
- Posts: 7312
- Joined: Wed Aug 10, 2016 6:56 pm
- Location: Florida
- Contact:
Re: Substrate / molting question - relatively new owner
Hello! Welcome to the HCA! 
Coconut husk is generally not recommended for the fact that 1) They can't make tunnels or caves in it and 2) They risk puncturing their sensitive abdomens with it.
Substrate should really be playsand and coconut fiber mixed to a 5:1 ratio. It should be mixed with dechlorinated marine saltwater or dechlorinated freshwater to make it sandcastle consistency. The depth should be a minimum of 6 inches or 3 times the height of your largest crab (whichever is deeper). I would recommend this in both of your tanks.
Yes, crabs do build a lot of tunnels, but when they molt they build caves. The caves are large enough for them to turn around in.
It is very possible that your substrate could be the reason that your crabs haven't molted. It could also be that they molted prior to you obtaining them, or that they did molt and you missed it
White hermit crab.. Sounds like you have had a molted crab. The color change can be the prior to the molt, or when they first come up from a molt.
Coconut husk is generally not recommended for the fact that 1) They can't make tunnels or caves in it and 2) They risk puncturing their sensitive abdomens with it.
Substrate should really be playsand and coconut fiber mixed to a 5:1 ratio. It should be mixed with dechlorinated marine saltwater or dechlorinated freshwater to make it sandcastle consistency. The depth should be a minimum of 6 inches or 3 times the height of your largest crab (whichever is deeper). I would recommend this in both of your tanks.
Yes, crabs do build a lot of tunnels, but when they molt they build caves. The caves are large enough for them to turn around in.
It is very possible that your substrate could be the reason that your crabs haven't molted. It could also be that they molted prior to you obtaining them, or that they did molt and you missed it
White hermit crab.. Sounds like you have had a molted crab. The color change can be the prior to the molt, or when they first come up from a molt.
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
Re: Substrate / molting question - relatively new owner
Thank you SO MUCH for your answers. A couple of clarifications.
Substrate: I'm not using coconut husk, it's much finer, more shredded than that. But I'll change it. When you say 5:1 playsand:coconut fiber, are your referring to coconut fiber substrate that looks a lot like dirt? Just want to make sure I use the right thing when I go to all the trouble to change out the tanks. And the end result will be mostly sand, right?
Molting/white crab: After scouring this website, I was sure that Charles was about to molt after he turned white. But he was never buried long enough to molt (either before or after he turned white). He is our most active/friendly crab, so we see him all the time. Don't they disappear/bury themselves for weeks or longer when they molt? (Note that he did turn white in the aquarium that is 100% coconut fiber substrate - soil, not the looser fiber that I prefer
Our crabs seem to eat a lot and often change shells, so we must be doing most things right. This is a very useful resource, and I thank everyone who contributes! While hermit crabs are extremely easy pets, we want to make sure that their environment is as fun and healthy as possible, and you really do give us all the information we need. THANK YOU ALL.
Substrate: I'm not using coconut husk, it's much finer, more shredded than that. But I'll change it. When you say 5:1 playsand:coconut fiber, are your referring to coconut fiber substrate that looks a lot like dirt? Just want to make sure I use the right thing when I go to all the trouble to change out the tanks. And the end result will be mostly sand, right?
Molting/white crab: After scouring this website, I was sure that Charles was about to molt after he turned white. But he was never buried long enough to molt (either before or after he turned white). He is our most active/friendly crab, so we see him all the time. Don't they disappear/bury themselves for weeks or longer when they molt? (Note that he did turn white in the aquarium that is 100% coconut fiber substrate - soil, not the looser fiber that I prefer
Our crabs seem to eat a lot and often change shells, so we must be doing most things right. This is a very useful resource, and I thank everyone who contributes! While hermit crabs are extremely easy pets, we want to make sure that their environment is as fun and healthy as possible, and you really do give us all the information we need. THANK YOU ALL.