Fish Disappearance

Hi

Over the last two weeks i have been loosing Fish on a regular basis and have no idea why there is no white spot or water problems and nothing wrong with my live rock or corals...

i have recently introduced a Engineer Goby into my tank and he is about 10" long and has found his home under some live rocks and i have a large tank with a lot of corals and rock.. anyway Ive been doing some research trying to find out if he is the culprit or not and there is a lot of people saying they are aggressive and a lot of people that say there fine...?

So far i have lost Powder Blue Tang, Sail fin Tang, Butterfly fish, 2 Sand Gobys, sweetlips. i have not seen any of these for days now apart from the 2 sand gobys i found this morning dead with what appear to be bite marks on there underbelly's. all the fish i have lost so far have been between 2" - 3" so there not big at all

The only other fish i have in my tank are a Fox face , 2 Clown fish, 4 blue damsels, brittle starfish, flame scallop & 2 cleaner shrimps


Any help on this situation would be greatly appreciated!

Many thanks
Brian

 

I had an two different engineer gobies (not at the same time) for years when my tank was a FO. After the fact, I figured out slowly over time that they were the most likely suspects in eating my small yellow tailed damsels and blue reef chromis that I would add to the tank. In terms of eating tangs over the smaller damsels you have, that's mysterious. But in answer to your general question, engineers can eat fish although appear peaceful when lights are on. Mine were a good 10 to 12 inches long.

 

Sorry for your losses. TO help figure out what is going on, could you provide the following info:

What size tank?
How long has it been setup for?
Have you seen any fish with any disease (Ich, Marine Velvet, etc.)?
What are your parameters (at least temp swings, pH, nitrates, salinity)?
What order did you add the fish, and how far apart?

This should hopefully help figure out what is going on.

 

Might be your brittle. They have been known to eat fish. I had one in my old tank that if not fed would catch and eat fish at night when they slept.

 

thanks guys 6ft tank all water tests are finehad setup 6 months lots of corals live rock all superb

 

Could be a hitchhiker that's all grown up. I'd check out the tank with a red light well after pitch dark and see what you can find. As far as I knew, I thought engineer gobies were bulldozers but were only thought to be killing fish by some because they were nipping at the dead bodies, but I could be wrong and have no experience. Either way, I'd still check out the tank at night.

 

Three things I've learned as an aquarist:

1) Fish love live food; if something live fits in his mouth, it's food.

2) A fish does not need to be a predator to eat another fish if it fits in his mouth.

3) "Peaceful toward tankmates" only applies to tankmates that don't fit in his mouth.

IMO, a 10 inch engineer goby + 2 to 3 inch tankmates = a buffet.

BTW, how large is the star? You may have more than one opportunist at work.

 

+1
You are very right!

 

occupants (past and present)
Fox face
Clown fish
Clown fish
blue damsels
blue damsels
blue damsels
blue damsels
brittle starfish
flame scallop
cleaner shrimp
cleaner shrimp
Powder Blue Tang
Sail fin Tang
Butterfly fish
Sand Goby
Sand Goby
sweetlips
engineer goby

A 6 foot tank doesn't mean much, that can be 100g or 500g. What kind of support equipment, skimmers, sump, reactors etc do you have. Saying water tests fine dont really help. What did you test specifically and what was the levels?

Without really knowing the size of your tank it sounds like a lot of fish. How long have has the tank been running and how long are you going between adding new additions?

You cant necessarily blame a predator as if there is something chemically or biologically killing them its the natural cycle of life that the other fish would be eating the carcasses. I'm not saying some sort of scavenger isn't the culprit but most don't go on mass killing sprees and generally kill what they can eat.

 

I must respectfully disagree, khowst. If there was a chemistry or water quality issue, the star, scallop, and shrimp would've been the first losses. According to the OP, they're all still alive and well even after 5 species of fish have vanished over a two-week period.

FWIW, I've had plenty of "reef-safe" scavengers that became opportunistic, and the serpent star is well-known for it. Also, as already indicated, having a 10 inch fish with 2 to 3 inch tankmates, one really should've expected such encounters.