Are horseshoe crabs easy to take care of? My lfs told me today that it would b a great addition to my nano reef. But when I aasked him if it would grow big he told me that they will not grow big for a long time. Is this true???? How long does it actually take for these guys to grow big???? I am not planning on getting one but I am curious. Afterall, they are cool critters! Don't worry I know that they are definetly not suited for a 24 gallon nano tank. Just wondering in case I am wrong.