Stress or Something Else?

[Goneaway562]

Hi all, figured I would post here to try and get some answers. I have had my Red Sea Reefer 425XL up for approximately 6 months with the current stock list:

- Banggai Cardinal
- Tail Spot Blenny
- 2 Blue Chromis
- Royal Gramma
- Kole Tang

All six of these fish have been eating and are all healthy without showing any signs of disease to my knowledge. I have tried adding another fish on three separate occasions (2 Sunburst Anthias and 1 Flame Angel) all without success with the fish dying within 1-4 days. The first Sunburst I added got picked on a bit from the tang, but the aggression died down after a few hours but a couple days later the Sunburst stopped eating and died overnight. The second Sunburst I added died within a day in the acclimation box and was pale most of the time when I added it. Lastly I added the Flame Angel and found the Tang chasing it around but with no visible damage only to find it the next morning being picked on by hermits.

Any idea what could be causing this? Stress from the Tang? I have read also that velvet could be an issue but all six of my current fish have been healthy for months.

Thanks in advanced and sorry for the long paragraphs!

 

[LesPoissons]

When you are adding fish you want to go from least dominant fish to most aggressive. Tangs and angels can be competitive for most aggressive, especially in that small of a tank. You also need to list your parameters so we can see if there's anything with the water quality going on. If your tank is only 6 months old and it might be a problem with incorrect cycling and the tank can only sustain so many fish without the ammonia creeping up.

Other factors- poor quality fish? Where do you purchase from? Acclimation process? Qt? Also most Anthias need to be fed 3 times a day at or they waste away rather quickly, though overnight is surprising.
If you want to add more fish you either need to take the tang out, change the rockwork around, and add it last or take it out altogether.

 

[Goneaway562]

When you are adding fish you want to go from least dominant fish to most aggressive. Tangs and angels can be competitive for most aggressive, especially in that small of a tank. You also need to list your parameters so we can see if there's anything with the water quality going on. If your tank is only 6 months old and it might be a problem with incorrect cycling and the tank can only sustain so many fish without the ammonia creeping up.

Other factors- poor quality fish? Where do you purchase from? Acclimation process? Qt? Also most Anthias need to be fed 3 times a day at or they waste away rather quickly, though overnight is surprising.
If you want to add more fish you either need to take the tang out, change the rockwork around, and add it last or take it out altogether.

Thanks for the reply. That was my one mistake at adding the tang midway through. I’ll most likely take it out temporarily or rearrange the rockwork. The place I buy the fish from quarantines for multiple weeks prior to selling them and I’ve never had any issues in the past with my 20g tank. As for acclimation, their salinity is typically 1.019. I float the bag for 20mins, then slowly drop acclimate until the salinity matches the tank. Unfortunately I don’t QT so that could be a problem. As for feeding Anthias, I know they require multiple feedings which isn’t a problem as I try to feed 3 times a day anyways.

As for parameters I don’t think anything is out of whack considering a few Acropora I have put in the tank are growing.

Salinity : 1.025
Alk: 8.1
Cal: 420
Mag: 1280
Ammonia: undetectable
Nitrite: undetectable
Nitrate: 5
Phosphate: 0.02