Aquarium Serial killers!

[GillMeister]

I had a Miniatus Grouper back in the 90's. As soon as it hit my tank it ate anything that fit in its mouth and it had a HUGE mouth. Huge.

 

[carbasaurus]

Years ago I had a juvenile squaretail bristletooth tang the made a habit of hovering above the goby caves and shiving them with his tail blade when they came out. Truly diabolical

 

[Singspot]

My Blue Hippo killed
1. Large Harlequin tusk
1. Large red corris wrasse

 

[TrampledByEwoks]

Had a pair of black percula clowns that were the only survivors of a tank crash. Everything I tried to add after that got killed off by clowns and had to remove them. Thought I was safe as they were the only fish in a 220.

 

[subawoo_kendra]

I had a massive sized emerald crab that was killing my fish off in my nano, ended up catching him and throwing him in my husband's big tank with his other emerald, he ended up trying it in that tank and got a nice surprise from the pistol shrimp and my emerald did take the hubbys emeralds arm off. so, we ditched it thing was mean as all can be!

 

[Theolox]

I once had a Wolf eel that woke up and chose violence against the tank. I got him out quick before he could eat my juvenile passer angel.

 

[Steph72]

Aiptasia! Wiped out numerous zoa colonies before I got it under control

 

[HermitCrab15]

The most murderous fish I've ever had is a coco damsel. his fish has turned every cleaner shrimp, hermit crab, and snail ever put into the tank into past tense.

 

[WallyB]

HERE IS A MONSTER (Photo Evidence of Murders) TIGER COWRIE

Here he is..... The Tiger Cowrie.

He was actually put in my Tank as a Green Hair Algae Solution. He won First Place in the Green Hair Algae Eatting Contest, which is an Experiment I did for GHA cleanup in a Test Tank, with Time Lapsed Camera & sample of GHA covered rocks. The Cowrie even beat the Sea Hare which was faster eatter but died quickly.

Here is the Timelapse video of all critters and their GHA polishing work. You see at 35 second mark him devouring a GHA covered rock.


So of course I put him in my GHA problem tank.

The Cowrie was fine for many months. He polished off Algae like crazy. Including tons of GHA. One day I started wondering what was causing damage to my SPS. Then I finally caught him in action shaving off polyps off a nice Neon Green Stylo.

I temporarily put him in a Frag tank without SPS......and he found something even more tasty before I could react. In a matter of a minute he sucked out the meat of a Beautiful Torch. I was horrified as it happend in front of my eyes since it was a prized Aussie Golden Torch. I took a photo rather than rushing to save the torch.... since it was too late.

I didn't toss the Cowrie. He was confined to my sump where he did amazing fine algae management for a couple of years. Sometimes I would tansfer him to my Algae Scubber to get extra food. He ate GHA right off the Scrubber Grow Screen. He eventually died of starvation (or age). I still keep his empty shell as a Lessons learned keepsake.

 

[Sasquatchv]

I used to keep African Cichlids. I had a beautiful breeding pair of Electric Blue Mainganos cichlids. I also had an Oscar in the tank. She (Mainganos) was holding a full clutch of eggs in her mouth. They had just hatched and were showing eyes and tails and starting to really squirm around so she was close - maybe another week - to spitting out a couple hundred dollars for me. Groucho decided she looked like an edible wrapper for all the caviar she was holding and decided he felt like having a snack. My wife sent me a picture of the Oscar with the tail sticking out...

That was karma punishing you for mixing malawi cichlids with Amazon cichlids known to eat anything they can fit in their mouths, snails incuded.

 

[tbrown]

That was karma punishing you for mixing malawi cichlids with Amazon cichlids known to eat anything they can fit in their mouths, snails incuded.

That was all my wife's idea. I also had Jewel Cichlids...

 

[Piscans]

I have a 6-line wrasse that ended 4 anthias, a striped blenny, a canary blenny, 2 skunk cleaner shrimp, 2 coral banded shrimp, and a mandarin goby.
When it was all going down, one of the anthias made an incredible leap into an adjacent tank 2 feet away... The canary Blenny and Striped blenny knew he was coming for them too because they were so sketched-out. I still have no idea what triggered him. I cant catch him out...

make a trap, or catch all the other fish, buy an anglerfish, let it eat the wrasse & catch the anglerfish & return it to the store.

 

[Greybeard]

My wife rarely shows much interest in my tank. We were at a shop some time back, she spotted a flame hawk, with the googly eyes, perched up in the rockwork, as they do. Thought it was real cute. Thing was small, a bit less than 2", maybe. Seemed healthy. I knew they had a reputation as a shrimp eater, but my skunk cleaner shrimps were all quite a bit bigger than the hawk... Hopefully, it'll be OK.

Nope.

Darned thing took out 4 of my 6 cleaner shrimps in two days. I tore the darned tank apart catching the devil fish... took him back to the store where I got him, and traded him for two skunk cleaner shrimp. Bad deal all the way around.

Had a flame angel in a reef that developed a taste for zooanthids. Took out entire colonies. I'll never have another Centropyge type angel in a reef. These days, I stick with Genicanthus family angelfish, and I'm quite pleased with the results. No, they don't have the bright colors of some of the Centropyge or Pomacanthus angels, but they're just as beautiful, in their own quiet way.

 

[Alex Costa]

Six line, pink tail triggerfish, Clown fish.........

 

[wolfen281]

Emerald crab that liked acro polyps but not the algae sticking to the rock next to it. -Sump Jail
Spiny Urchin- cool hitchhiker from a live rock order- lawn mowered half my Princess Peach acro - Sump Jail

 

[Jillianh]

Giant Mexican Hermit crab named Say-Tan. The thing would eat anything mom-motile or that wasn’t fast enough to get out of the way. I admit it was an impulse purchase. This is what happens when you don’t have an LFS and end up wanting one of everything (but know better) when you finally end up in a Petco.

 

[Sasquatchv]

I would like to change my vote.
My banded shrimp named Rocky just went after yellowtail blue damsel, luckily small guy(1.5") hid in aquascape and suvived unscathed. Rocky clearly didnt like eating leftovers, still some on the bottom, fed him some prawn and damsel is safe, for now .

 

[JKBrown]

Nothing that I have caught, but I have lost a couple of types of Zoas while others were untouched.

Laughing at the search-engine alarms that must be going off reading this thread!

 

[TinCanHero]

vermited snails. without a doubt one of the worst pests you can get, totally under-ranked and overlooked.

Other than that my second 6 line went on an instant rampage when I added my mandarin and long-nose hawk.

 

[sfin52]

This is Elsa and she was a killer. Not only did she try to murder my hand but she did kill 3 fish.
Apon introduction to the tank she was being bullied by blue green cromis and a coral beauty. I almost pulled her than a flip was switched. Day three I come home to a serverly beat up green cromis. It died shortly after finding it. I come home the next day a second cromis was in the same condition. The coral beauty hadn't learned and was still trying to pick on Elsa and she was standing her ground. I come back from work and the coral beauty was absolutely beat up. Fins all ripped up scales missing and all. There was Elsa swimming around all proud of herself. All the other fish kept thier distance. She now was the queen of the tank

Coral was now on her list. If she didn't like placement she would let me know. Push them off pick them up and dump them on the other side of the tank. At the same time trying to rip my hand apart.