Mantis shrimp? My tank knocks!

So i was reading through some threads and came upon one talking about mantis shrimp. I have had my tank up for a year and almost everyday i can hear a knocking noise coming from my tank. Its not quiet.(i can hear it from across the room) it will knock a few times, never really paid much attention to it at is until i came upon this thread. Any ideas? Where do they hide?

 

Pistol shrimp make noise too.

 

I have kept mantis and pistols for over a decade. Based on your description, I don't know what you have. Heck, some people have vocal clownfish, vocal puffers, clumsy snails or hermits.

But in spite of what you've read, there are sooooo many old wives tales about mantis and pistols that it's downright hilarious. In other words, don't worry about it.

 

i used to have a domino damsel that could do a 180 degree turn so fast it made a audible sound like a small switch.
i used to joke it would break the speed of water

which makes no sense but it doesn't have to

 

Till you start missing tank mates! then my advice to you would be to remove rocks one by one till you find it

 

I HAVE THE SAME PROBLEM, and i hope its not stressing my clowns,

what i think it is is that it usaully happens when i turn my lights fully off, or somtimes down to the 2 actinics, i think it may be the fixture or the brace in the tank it cracks because it is cooling down quickly and the molecules that the light fixture or brace are made up of make a snapping noise because they are rapidly coming back together .

heating = expanding
cooling = contracting


its like in a car, when you park it after a long drive and turn it off if you sit for a minute and listen you will hear all kinds of creaks and snaps coming from the engine bay... those creaks and snaps are the metals and plastic cooling and they are contracting in size...
catch my drift?

i THINK this is what it is on mine... may be the same thing on yours? other than that i cant even think of what it could be...

but i hear the NoIsEs too

 

uhh that doesn't sound good, pun intended;D

 

probably not a mantis. I hear noises from my tank every once in awhile, but i might just be imagining things.

 

yea but for me and what sounds like him too its pretty loud and i can hear it from accross the room and i doubt even a mantis could make such a big noise..

 

VERY LARGE mantis can and fairly small pistol shrimp can