Several of our octo keepers have had octos with missing arms. Carol's (corw314) Gimpy is probably the most recent. I believe it was about 4 months to grow back, althought the regrowth started right away. Could vary by species and arm length. The arms when regrown are reported to be slightly shorter than the original.
Thanks Nancy,, this bimac is still prety young. Its mantle is only about the size of a rubber bouncy super ball. Its got alot of growing to do yet so I think it will grow pretty quickly.
I shouldnt have put in that big hermit..... Its in a shell about the size of a golf ball. The bimac disappeared all the way inside the shell with the hermit,,, came out 10 min later and I thought he just had the meal of his life. hour later the hermit is crawling around. It is just too big for him. Down to the fuge he goes until bimac grows old enough to have his revenge!