Care for larger crabs

[jackiehermitcrab]

Hi there!

New to the forum, but we've had our hermit crab for 2 years.

Current set-up:

1st tank:
A tennis ball sized purple pincher in a 30gallon tank. Temp/humidity hang around 72/70+/-. Had this crab for 2 years. He did have a roommate, but the roommate went under to molt, never came back up. Gone. Not sure if Hermie killed him and ate him, or just ate him after molting. He was showing some aggressive behavior towards him prior to his molting.

2nd tank:
4 very tiny hermit crabs. We've had them about 6 months. All 4 went down to molt. 3 have come back up. Have not seen the 4th in a long time. Thinking he might have died during molting. Not sure.

Care questions:
1. We have 3 heaters attached to each tank and I cannot get the temps above that 70 mark. What am I doing wrong? They are attached on the sides and back. I have a glass top. I don't get it! Send help!

2. Is my big crab lonely? He is active at night, but he is so large, I don't know even where to get another crab his size as a friend. He was aggressive towards the last medium friend we put in and as mentioned, he is now gone. Is he ok alone? Thoughts?

Thanks for the help!

[HermitGuy3]

1: if you have an ultratherm or fluker's heating pads, you can insulate them to bring up heat with a car windshield sun protector thingy. If you have a heat pad that already has the sticky attached when putting it on, don't insulate it because it is a fire hazard. You can also put a blanket on top. How deep is your substrate and what is it?

Your crab is not lonely and dies not need a friend, but you can get him one. However, if there was aggression than there was likely something wrong with your tank. If you have purple pinchers, you should get them some Mexican turbo shells, which are their favorite type (if you don't have them already) . I like to order from Nessastores! You could also add more animal protein. Make sure not to add a friend until you fix stuff. ( if not already there)
Also, crabs do not need to be the same sizes to live together!
Adopt, don't shop!
Welcome to the forum!

[wodesorel]

What kind of aggression were you seeing with the big guys? Hermits decompose exceptionally quick if they pass when molting. There is an extremely good chance that your remaining crab had absolutely nothing to do with the other going missing. The only time to really suspect that being the case is if the molter had been separated from its shell, or you were actually able to witness the attack. Accidents can occur in tight quarters as well, from digging crabs basicly tripping over molters underground - not purposely seeking them out. Killer purple pinchers are out there but it's very rare, they tend to be a really social species.

As far as temp, what brand of pads are you using and what sizes? Some of them unfortunately don't do much in the heating. We usually recommend one laminated type UTH (ultratherm or flukers) that spans the entire length of the tank and covers at least the space above the substrate. If the room is cooler than US average (like 68F or so) then it usually needs to be insulated (when safe) for a boost.