What's Killing My Inverts?

[eraserhead187]

For the past few months, I can't keep shrimp or crabs, except some hermits, but even those occasionally seem to be getting killed. Something has decided to start picking them off one by one. I have lost a fire shrimp, 2 cleaner shrimp, 2 emerald crabs, and I assume a pom pom crab. The last one I never see, but I can usually find him if I try hard enough by shining a small flashlight into crevices. No such luck for a month or two though.

My stock list is:
2x stubby maroon clowns
1 coral beauty
1 flame hawkfish
1 neon dottyback
1 pincushion urchin
1 brittle star
Standard CUC fare
3x RBTA
1 maxi mini nem
1 rock flower nem
Mostly LPS and softies

I believe I have also lost a hermit crab that got pretty big. He used to be out all the time torturing the other hermits, but I haven't seen him in a while. Everything else is thriving.

Could it be the hawkfish? I used to see him harassing one of the cleaner shrimp several months ago. Most of the time, there is just no trace of whatever has gone missing, but today I found the body of an emerald crab that wasn't eaten yet. Anything sound suspicious from that list? Never had any problems until quite recently.

 

[jeffchapok]

My money is on the brittle star. How large is it?

 

[Gareth elliott]

Hawkfish will eat small shrimp, like sexy shrimp size.

Also Inverts ime require more acclimation than fish or corals. Another idea would be to run some carbon in case of any contamination

 

[dansreef]

Money is on the Flame Hawk. They have an appetite for shrimp and crabs. I have seen them go after both with vigor. The larger hermit could have been picked off shortly after molt or while trying out another shell.

I have a monster brittle star and they like to go after dead stuff. I havent seen him go after something live, though it is possible if it were able to corner a crab or a shrimp.

 

[eraserhead187]

None of the inverts have died right away. They always last a while, weeks or months. The exception was this last emerald crab, he was only in about 2 weeks. I had two cleaners that lived for about 6 months or so, perhaps the hawkfish got himself a taste of shellfish and decided he was a fan? Since those two disappeared, it's been fairly steady. I do run carbon as well. The hawkfish is a pig and I probably wouldn't put it past him. I would give some thought to the brittle star, but the two fire shrimp liked to hang out underneath one of the RBTAs, which I've never seen the star go near for some reason. They usually stayed pretty high in the tank. The hawk is a bit insane, he disappeared for a while until I found that he had somehow jumped into the overflow and was underneath the return pump. Weirdo. If it is him, I guess I'm just going to have to accept the idea that I can't have shrimp. He's just too fun to watch.

 

[eraserhead187]

My money is on the brittle star. How large is it?

He's a decent size. With arms fully outstretched, maybe 6 inches?

 

[eraserhead187]

Hawkfish will eat small shrimp, like sexy shrimp size.

Also Inverts ime require more acclimation than fish or corals. Another idea would be to run some carbon in case of any contamination

I used to see the hawkfish bully one of the shrimp if he didn't like where the shrimp was going, but never saw him actually attack anything. I've always acclimated inverts carefully, and I do run carbon as a general rule.

 

[eraserhead187]

Also should note, I did find some snail guts sitting atop my bubble coral the other day. So something may also have a taste for snail as well. They were ripped right out of his shell. I always blamed the big hermit crap when I found empty snail shells, but now I am starting to wonder.

 

[Gareth elliott]

Also should note, I did find some snail guts sitting atop my bubble coral the other day. So something may also have a taste for snail as well. They were ripped right out of his shell. I always blamed the big hermit crap when I found empty snail shells, but now I am starting to wonder.

Ever hear any clicking in the tank?

 

[eraserhead187]

Ever hear any clicking in the tank?

Nope, just the occasional sound of a hermit bumping his shell against the glass.....

 

[ReeferBean]

I recently added a Flame Hawk to my system. Within a week the two cleaner shrimp I had for a while are MIA. My money is on the Flame Hawkfish. I'm not positive but timing...

 

[PursuitOfHappiness]

For the past few months, I can't keep shrimp or crabs, except some hermits, but even those occasionally seem to be getting killed. Something has decided to start picking them off one by one. I have lost a fire shrimp, 2 cleaner shrimp, 2 emerald crabs, and I assume a pom pom crab. The last one I never see, but I can usually find him if I try hard enough by shining a small flashlight into crevices. No such luck for a month or two though.

My stock list is:
2x stubby maroon clowns
1 coral beauty
1 flame hawkfish
1 neon dottyback
1 pincushion urchin
1 brittle star
Standard CUC fare
3x RBTA
1 maxi mini nem
1 rock flower nem
Mostly LPS and softies

I believe I have also lost a hermit crab that got pretty big. He used to be out all the time torturing the other hermits, but I haven't seen him in a while. Everything else is thriving.

Could it be the hawkfish? I used to see him harassing one of the cleaner shrimp several months ago. Most of the time, there is just no trace of whatever has gone missing, but today I found the body of an emerald crab that wasn't eaten yet. Anything sound suspicious from that list? Never had any problems until quite recently.

My dottyback was violent!! He hated everything in the system, Extremely well fed but still did his best to harasse everything but my maroon. How large is the system?

 

[S-t-r-e-t-c-h]

I don't know. I'm hesitant that the hawkfish is involved. I've never seen them go after something like an emerald crab, for example. They're just not equipped to consume a crab.

Have you done any ICP testing? Things like shrimp can be the first to show signs of heavy metal toxicity. I'd start there. That the emerald was intact is the clear sign there. Then maybe start scanning the tank at night for any oddball invaders like mantis or bobbit worms...

It's also completely possible that it's all coincidence, BTW. CUC are notorious for short tenures in the tanks. Shrimp only live a couple of years total, so if you had them for a half a year but bought them on the large side, they may have been at the end of life to begin with.

Good luck...

 

[eraserhead187]

I recently added a Flame Hawk to my system. Within a week the two cleaner shrimp I had for a while are MIA. My money is on the Flame Hawkfish. I'm not positive but timing...

I don't know. I'm hesitant that the hawkfish is involved. I've never seen them go after something like an emerald crab, for example. They're just not equipped to consume a crab.

Have you done any ICP testing? Things like shrimp can be the first to show signs of heavy metal toxicity. I'd start there. That the emerald was intact is the clear sign there. Then maybe start scanning the tank at night for any oddball invaders like mantis or bobbit worms...

It's also completely possible that it's all coincidence, BTW. CUC are notorious for short tenures in the tanks. Shrimp only live a couple of years total, so if you had them for a half a year but bought them on the large side, they may have been at the end of life to begin with.

Good luck...

You have a good point with the CUC. It has been a good while since I have replenished them. Actually have an order from reef cleaners arriving tomorrow or Thursday. But still, the snail meat on the coral gives me pause.

I will look into testing for heavy metals, but I am not sure how they would have been introduced. I've always used RODI water that is meant for human consumption that I purchase, and it always gives me 0 TDS when I check it. I get that heavy metals won't show up in a TDS test, but there'd be bigger problems than shrimp dying if this water had heavy metals! Not sure what ICP testing is, but I do give the office a good wakkthrough every afternoon before I leave to make sure there are no Juggalos hiding out =)

I figure if it were an issue with some kind of nasty toxin, that the starfish would have bitten the dust by now. All I've got left is aggression. Certainly could be some little monster that lurks at night... The Emerald was intact insomuch as I grabbed him out of the tank and tossed him, but I didn't give him a thorough once over to check for damage. Probably should have done that.

Unfortunately I don't really have access to the tank at night, except via a crappy Webcam because it's at my office. I certainly wish I could just head over there at night when the kids are pestering me, but my wife probably wouldn't be pleased!

Thanks for the help!

 

[eraserhead187]

My dottyback was violent!! He hated everything in the system, Extremely well fed but still did his best to harasse everything but my maroon. How large is the system?

I have heard that about dottybacks, and realized that after I had tossed him in. I started to freak out trying to figure out how I was going to get him out if he ended up being mean, but I lucked out so far. He's at the bottom of the pecking order in the tank. The clowns are in charge.

The tank is a 32g BioCube with a bunch of upgrades.