Disappearing fish

[tuajia]

Hi all. Have a strange situation to deal with. I have a 4ft tank FOWLR with fish below 4" size for about 3 years. It contains the following livestock:

 

1. Red banded shrimp

2. Cleaner shrimp

3 tailspot blenny

4. Yellow coral goby

5. Pincushion urchin

6. Freckled hawkfish

7. Six line wrasse

8. Narcissus Snail x 3

9. Some random brittle stars (10 cent sized body)

 

Over the last 2 months, I have tried adding different fish into the tank but all have been mysteriously attacked. I will sometimes observe the fish looking stressed and having fin or scale damage one day, then next day they are missing. So far I have the following fish issues in sequence:

1. Laboutei wrasse 3" (missing)

2. Mcosker flasher wrasse 2" (missing)

3. Lubbock's wrasse 3" (rescued)

4. Firefish 3" (missing)

5. Naoko wrasse 3" (rescued)

 

So far it seems like I am unable to add more fish unless I isolate the problem. The 2 wrasse I rescued are housed in a separate partition with a dwarf lion, no problems so far as they are same size.

 

Any idea who the culprit is? I only observed the 6 line wrasse (only 1.5") bullying the wrasses so I isolated it, but the attacks continued. The tank is loosely covered with plastic mesh, at least 90%. So chance of them jumping out is also low. I tried spying on the tank at night with a red light bit so far didn't see anything weird. The only strange thing I observed is the Naoko wrasse sleeping on the sand and the narcissus snails where crawling on top of it. I'm really running out of ideas what it could be. Hope all sifus can advise. Thanks!

 

 

Sent from Singapore Reef Club mobile app

 

 

[tuajia]

Forgot to add some pics for better visualisation.

Sent from Singapore Reef Club mobile app