Crab Streaking for 4th time

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Crab Streaking for 4th time

Post by indimitable » Wed Jun 17, 2020 1:58 am

I did GB for GotButterflies

Since you've come to the emergency forum, we know you want a fast answer to your question. In order for us to figure out the problem as quickly as possible, we ask that you answer the following questions as best you can. Some of them may seem odd, but they're all designed to give us the information we need to give you a good solution for your problem. The things in the [ brackets ] are there to make this post easier to read once submitted. Thanks!

1. What kind of substrate is used in your tank and how deep is it?
Approximately 5:1 ratio of playsand to eco earth, moistened to sandcastle consistency (2 of our crabs love digging in it and seem to think it’s the perfect consistency).

GB: Great! IMO, for purple pinchers substrate should be 6 inches or 3 times the height of your largest crab (whichever is deeper). If you have Es substrate should be at least 10-12”. Substrate should be mixed with dechlorinated marine saltwater or dechlorinated freshwater to make the substrate sandcastle consistency. I personally mix mine with dechlorinated marine saltwater.

2. Do you have gauges in the tank to measure temperature and humidity? If so, where are they located and what temperature and humidity do they usually read?
Yes- digital ones that hang just above the heaters on the hot side, which tend to be 80-84F and 72-75% humidity (it’s right above the water pools as well). We also have analog ones that are on the cold side, which tend to be 71-80F and 75-85% humidity (above some moss).

IMO, minimum heat and humidity should be 80/80. Hermit crabs have modified gills and need the humidity to breathe. As far as cool sides - It's okay for it to get a little cooler at night. I personally keep my temps 80-85. My humidity goes as high as 99%.
Humidity boosters: Bubblers definitely do help boost the humidity. Double dish bubblers: ... r#p1030806

You can also add moss pits to help. You would use organic moss (as well as moss that is on the safe list), and moisten it with dechlorinated fresh water. Then, put the moss in a shower caddy or a glass vase laying on it's side so the hermits can walk in and out of it. Glass tops also help keep humidity in.

You can buy an Acurite guage from Amazon, digital, runs on batteries, tells you temp and humidity currently as well as low and high for last 24 hours: ... 184&sr=8-2

3. Is a heat source used in the tank? If so, what?
Yes- two ZooMed heating pads on the back wall.

GB: IMO it would be better if you could get your heat up to at least 80. You can try to insulate around your heat pad with aluminum foil (shiny part facing the crabitat), then cardboard. Don't insulate over your heating pad if it is a zoomed. If doing the insulation doesn't raise your temperature, you might want to consider getting a better heater. Most of us use ultratherms. They are great heaters. or sells them.

4. What types of water are available (fresh or salt) and how is the water treated (what brands of dechlorinator or salt mix and what ratio is used to mix it)?
Pools (deep enough for the largest crab to submerge fully including shell), one saltwater and one freshwater, with fake aquarium plants to climb in and out. Brand is ZooMed, we use the recommended ratio (1 teaspoon saltwater per cup of water, 2 drops freshwater conditioner per cup of water). We replace it every 2 days or if it gets very dirty in there.

GB: Unfortunately most products marketed for hermit crabs are not safe. A lot of us use a product called Instant Ocean which is what aquarium hobbyists use to make saltwater aquariums. It has the essential trace elements that hermit crabs need. :) You need a dechlorinator that removes chlorine, and chloramine as well as neutralizes ammonia and heavy metals. A lot of us use a product called Prime. As far as salt, you need marine salt, to mimic the ocean. You have to use the dechlorinator for both freshwater and marine saltwater. Both pools should be deep enough for them to fully submerge in and safe enough for them to get out of.

5. What kinds of food do you feed and how often is it replaced?
We follow guidelines from here and the Crabstreet Journal. We try to keep it varied, with some sort of protein daily. We’ve never seen them eat or seen large chunks of food disappear so hard to tell what they like, with the exception of tomato (at least we know one of them likes it). They most commonly have dried shrimp, dried mealworms, dried coconut (hoping to feed fresh this summer), fresh fruits and veggies (lots of banana, strawberry, tomato, and lettuce), hard boiled eggs, egg shell, cooked chicken, honey, and dried bugs. We replace it every 2 days as it tends to mold quickly (lots of condensation in there as they’ve only been in this tank for a while).

GB: Hermit crabs can eat a lot of the same things that we eat. Just check to make sure the item is on the safe list. Foods should be organic when possible. Hermit crabs are sensitive to pesticides and fertilizers.
You also want to provide one or more calcium sources at a time. Examples would be Cuttlebone, Organic Eggshell, Oyster Shell, Lobster Exo, Shrimp Exo.
Make sure you cover all aspects of food pyramid :)
Safe food list: ... 25&t=92557
Unsafe food list: ... 25&t=92556
Food pyramid: ... 25&t=92554

6. How long have you had the crab and what species is it, if known?
We have 3- we got Johnny in July, then got Carla and Diego (Diego is the one we’re worried about) in November. All are PetCo purchases, and we’re fairly sure that all 3 are purple pinchers due to coloring although the least sure about Diego.

7. Has your crab molted, and how long ago did it happen?
We believe he molted somewhere between 3 months and 3 weeks ago.

8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?
40 gallon breeder glass aquarium, with a glass lid. Lid is kept closed as much as possible.

9. How many crabs are in the tank and about how large are they?
3. Diego and Carla are the same size, and fit comfortably in shells with openings .5-.3/4”. Johnny used to be their size and has grown considerably lately, he has a favorite shell that has a 1-inch opening (but is a bit too big for him).

10. How many extra shells are usually kept in the tank, if any?

GB: Here is the shell guide: ... 24&t=92552

11. Have there been any fumes or chemicals near the crabitat recently?

12. How often do you clean the tank and how?
We wipe condensation when we see it, and take out moldy sand.

GB: You shouldn't have moldy sand. Do you have mold growing in your tank?

13. Are sponges used in the water dish? If so, how are they cleaned?

14. Has anything new been added to your crabitat recently?
The whole crabitat is only about a month old- we had them in much poorer conditions before (screen lid, bad humidity, etc.). We added a new cork wood hut a couple weeks ago but it molded a lot so we took it out after only a couple days.

GB: You can soak the cork bark in marine saltwater and then dry it out in the sun if you wish. This will help it prevent mold growth in the future.

15. Is there any other information you would like to share that might be helpful (anything that is regularly part of your crab care, playtime, bathing, etc.)?
We try not to touch them much, and leave the lid closed as much as possible. Carla and Johnny have been thriving upon moving to the new crabitat. Nothing in the crabitat is painted (including shells) or should be toxic, we’ve tried to be really careful with it.

16. Please describe the emergency situation in detail.

Tonight for the 4th time we found Diego out of his shell. All times, we’ve found him hiding in the aquarium plants that are designed to be ladders out of the pools- they have long vines that trail onto the substrate and provide cover. He wasn’t very active before, but we chalked it up to the poor crabitat and worked to get a better one. When we moved him to the new one, we noticed he was paler than he had been and there’s a dent in his big claw- we thought maybe a molt gone wrong and a fight? Everyone was in their favorite shells though, and they normally don’t interact with each other much. Johnny and Carla will explore the same log sometimes and rest on top of each other, but don’t do much else together. We put them all in the new crabitat and resolved for observe them, and then he started streaking! The first time, we washed his old shell and put it next to him and left him alone- he was back in it after a couple hours. The second time, we didn’t wash it (didn’t know how important it was) and he was back in it after a couple hours again. The third time, we washed his old shell and he chose a new one that he’d never used before (Carla’s original shell). The fourth time is tonight- I came to check on them after work and he was naked, with Johnny near him. Johnny hid when he saw me, and I couldn’t tell what he’d been doing before. I moved Johnny and went about replacing the food and water as I normally do, thinking I’d look at naked crab advice after doing that. When I put the saltwater back in, he took interest and started walking around it- he tripped and fell in, landing on his back. He struggled for a few moments, didn’t flip over, then stopped moving and fluttered limply. I felt nervous touching him so I used a very large shell to gently scoop him out and place him on the substrate near the pool. He skittered away from me and started trying to climb the wall, then settled down when I moved away and hid in the plant for a moment. He’s currently hanging from the plant above the water, which he’s been doing when he gets naked. My partner worries that he’s too weak to move with the shells on, especially to get in and out of the water. The other crabs have each gone near him once while he’s been naked tonight (about an hour now, with me staying near the whole time) but lost interest and moved away without getting closer than a couple inches. We read the shell-less crab guide and are about to try putting him in a cup with some water and freshly washed shells, plus some honey. He’s currently dipping the end of his abdomen into the saltwater. We are worried that it keeps happening, and that in the month he’s been in the new crabitat he hasn’t gained much color or strength. Johnny and Carla are both a healthy red with vibrant purple claws, and he’s a light pink-red with maybe a lilac claw. He used to be pale when we first got him but not this pale (all 3 of them had color improvement after coming to us).

GB: More than likely all of this is due to PPS (Post Purchase Stress Syndrome). Hermit crabs go through a lot to get to us. Taken from the wild, held in filthy conditions deprived of space, sufficient food, water to bathe in. Sometimes forced out of their shell. Then shipped to another supplier, then shipped to a pet store, then you take them home. That is a lot of environments to get used to. Until a hermit crab has molted with us a few times, any death during that period is likely PPS. I do recommend getting your humidity up and purchasing the right kind of dechlorinator and marine salt :) It is also imperative to provide calcium all of the time. Best wishes. If you have any questions we are here for you!

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Re: Crab Streaking for 4th time

Post by indimitable » Wed Jun 17, 2020 9:43 am

Unfortunately Diego refused a new shell and passed away last night. If anyone has any insights into changes to make for future crabs (we planned on getting more even before this), we are all ears!

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Re: Crab Streaking for 4th time

Post by curlysister » Wed Jun 17, 2020 9:58 am

I am sorry to hear that he passed away. Were you able to gain any insight from the naked crab care sheet?
It could be that your crab simply ran out of energy from previous sub-optimal conditions, like is the case with PPS. The only change I would make in your conditions is to use Instant Ocean instead of the Zoo Med salt water (the Zoo Med won't have all the necessary minerals).
"If there are no dogs in Heaven, then when I die I want to go where they went." -Will Rogers

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Re: Crab Streaking for 4th time

Post by indimitable » Wed Jun 17, 2020 8:11 pm

We printed off the sheet to have on standby in case it happens again- as we plan on getting more this might not be our last time dealing with PPS.

Thank you for the Instant Ocean recommendation! Will look into switching over when this one runs out.

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