ok I did it I order these two and didn't even think to find out if they get along or will one kill the other - horseshoe crab came with newpaper between the two bags now I'm wondering if it was so they couldn't see each other or if they are just more light sensitive
I have only had mine since tuesday. I have both cleaner shrimp and horseshoe crabs. So far I havn't lost anyone so I assume they will get along. Todays the 1st day that I've seen the horshoes out durring the day. When I 1st added them they only came out at night. I don't know about the newspaper. I wondered that myself.
I have had 2 small horseshoe crabs for about 2 1/2 months now with several shrimp in the tank and have had no problems. The horseshoe crabs actually do a nice job of stirring up debris on the cc bottom. I guess since the horseshoe crabs are basically scavengers that they are just not interested in the shrimp. good luck.