Is it the filter?

[Bocray]

I have had several deaths in the last few weeks with newly introduced blue green chromis after their bodies showed up perfectly severed as if by a blade I decided it had to be one of my shrimp after removing all my shrimp it continued. I have watched my tank at night no unknown hitch hikers or anything capable of cutting one of my fish in half perfectly. The only other option looks to be the filters...
I have a BaK PaK protein skimmer a wet dry trickle filter and a power head.

Ideas?

please help.

 

[Kurt_Nelson]

Sure sound like a Mantis Shrimp to me.

 

[Jason7894561230]

Mantis shrimp Also have you heard any clicking noises that would indicate a mantis shrimp

 

[Bocray]

Thank you for your replies
I will watch to see if there is a mantis however I know that none of my known shrimp are mantis and could a mantis really chop a fish in half cleanly?

Edit:
I do hear clicking noises at night but i have a smaller tank with several tiny pistol shrimp that hitchhiked in.

 

[Bocray]

Update:
Due to a small wiring explosion only my protein skimmer is working though nothing has happened to the chromis

So it is either the wet dry trickle filter or the power head chopping my fish

 

[Kurt_Nelson]

Or a Mantis...

 

[Bocray]

Update:
Due to a small wiring explosion only my protein skimmer is working though nothing has happened to the chromis

So it is either the wet dry trickle filter or the power head chopping my fish

If it was a mantis why would it stop killing my fish when there was no power to the power head and the wet dry trickle filter?

 

[Kurt_Nelson]

Because it hasn't been hungry for the last couple days?

I'm just not seeing how a wet/dry filter can chop a fish in half, and I'm not aware of any powerhead that can act like a meat cleaver and perfectly slice a fish in two. From your description, a couple of us thought "mantis", and after seeing the picture I'm even more convinced. Do some Googling on "slasher mantis". There are two types... "slashers" and "bashers".

I hope it isn't a mantis. Just saying that I wouldn't rule it out so easily.

 

[Bocray]

Thank you for your replies,
I will keep a look out and set some traps for a mantis shrimp.

I can see how you would think it would be a mantis, something that only attacks my fish leaves my shrimp alone, but any ideas how it could have gotten in to my tank, I haven't introduced any live rock into my tank recently only base rock. Could it really stay undetected for so long?

thank you for your replies

 

[Deep Seven]

Reading up on mantis shrimp they have a long and complicated lifecycle. They have a plankton form/phase, and go through a metamorphosis, actually they go through about 7 stages before reaching sexual maturity.

Have you added any corals, live rocks, or water from a foreign source in the last 3-6 months?

I would try covering your powerhead or whatever else you may suspect in a mesh bag or pantyhose. If your powerhead is the cause this should solve it.

 

[Tank2379]

I also agree on a Mantis Shrimp- you should probably google mantis shrimp and your read all sorts of issues with the same question you have and it turns out to be a mantis- They are very good hiders and are fast- Most hunt at night or if extremely hungry they will come out during the day to look for food...

 

[Bocray]

Thank you for the fast replies, I love this forum!
If they can come in on live rock from 6 months ago than yes that is a possibility
Okay so if this is a mantis how do I trap it, will the glass jar method work? Do I have to camp out with net and flashlight?

 

[Bocray]

So I am going to try the inverted bottle method, with some slightly freezer burned shrimp. Any other traps I should try?

 

[David S]

what fish have you left in the tank?if juat a few could you rehouse them in a QT then starve the mantis for a bit and then try the bottle trap

 

[Bocray]

I have no fish currently in the tank. I will try starving the mantis. However If the mantis does not rear it's ugly head I'm thinking of getting a snowflake eel or octopus. And using the QT as the fishes permanent home.

 

[Bocray]

GAH!
I was looking around in my quarantine and I saw a mantis shrimp. In the morning one of my fish was gone.......
What do I do? The traps haven't worked and I didn't see witch rock it's burrow was in....