first one is a common bristle worm, you probably have more of them in your tank. its a harmless scavenger that eats detritus but keep you water parameters in check and don't over feed because they can multiply and over take a tank which could lead to problems.
second ones are pistol shrimps some people like them some people dont. they tend to have a symbiotic like relationship with gobies which is pretty neat. they can be harmful to some corals and slow fish but rarely ever
second ones are pistol shrimps some people like them some people dont. they tend to have a symbiotic like relationship with gobies which is pretty neat. they can be harmful to some corals and slow fish but rarely ever
