[joecon]

Hi folks,

I just bought a small Naso Tang (2.5 inches) about 3 days ago. She hasn't been eating and now has a pinched belly! I threw in some mysis shrimp, formula 2, dried seaweed (nori, spirulina) and tang formula (not sure of name). She would eat whatever would "float" by her, but will not actively go after the food. She seems like a passive eater.

Water parms are perfect and she was acclimated VERY slowly with lights out. She isn't hiding, she just isn't really actively eating. Is she on her way out????

Thanks!

[zhenya]

Joe,

I moved your thread to this forum for expert opinion. Good luck with your fish!

[leebca]

Wild caught healthy well fed fishes can last several weeks without eating. Fish do not carry their 'fat' in their belly. Extra energy is stored on the dorsal side of the fish, most of the entire length of the fish.

A starving fish is one with a pinched dorsal area.

The best acclimation for a Tang was the one I've recommended here: It Was Acclimation, I know. . .

After the fresh water dip the Tang is put into quarantine where a treatment using Cupramine is done. After this, the Tang in the QT settles in nicely.

If the Tang is now in your display tank and the fish isn't eating, it is because the fish is stressed. A Tang should not be bought and put into a marine aquarium until that aquarium is about 8 months old. This is because the aquarium is going through many changes during the maturing phase. See this: The Mature Aquarium

Unless I understand and know more about your system and fish, I can't help you out very much other than to say to find and reduce the stress that is on that fish. If you would like further help in finding that stressor(s) then I'd need to know:
Where did you get the fish from? LFS? online? How long did they have the fish?
You have this fish in your 75 gallon tank?
Provide me the list of all other marine life in the tank with the Tang.
List your equipment: do you use a skimmer? a mechanical and/or chemical filtration system?
What is your biological filter?
How old is your aquarium?
What kind and thickness of substrate do you have? Describe your system.
When did your aquarium first get set up and when did it cycle?
Do you have live rock in the aquarium? How many pounds of it is there?
Do you have a sump; a refugium?
Is your aquarium a reef aquarium or a FO aquarium?
I need to know the actual measurements and numbers for the following:
temp (and what range it usually stays within)
specific gravity
pH (tell me how you measured this)
ammonia (tell me how you measured this)
nitrite (tell me how you measured this)
If you are performing any of these tests, please tell me what the actual measurements are and how you are getting the measurements:
phosphate
nitrate
alkalinity
calcium
magnesium
Are you adding anything other than food into the aquarium?
Other than this fish, what other marine life have you added during the past 6 weeks?
Have you done any maintenance or changed any equipment lately?

You can tell from the above list that there are plenty of sources of water quality issues other than the things you watch. Since it could be a water quality matter, I suggest you perform a 60%+ water change as soon as you have new water ready. The fish could respond well to new salt water. Are you very careful about making water changes properly? See this: how do I do a water change? Tangs are very sensitive to changes in pH and they prefer a higher pH of about 8.3 or 8.4

Let us know if we can help! Good luck!

[joecon]

Hi Leebca, thanks for all the reference material!!! To answer your questions:
Where did you get the fish from? LFS? online? How long did they have the fish?
I got it from a huge local LFS and they had the fish for aboout 3 weeks (it was eating at the LFS. I asked them to feed it before I bought it and it ate voraciously).

You have this fish in your 75 gallon tank?
Yes. I know 75g is too small. The fish is only 2.5" I will have my dream tank of over 200g by this summer in addition to the already 75g I have

Provide me the list of all other marine life in the tank with the Tang.
Small yellow tang (about 2")
Flame Angel
juvenile black&white heniocus
and a small cream angel (also 2.5")

List your equipment: do you use a skimmer? a mechanical and/or chemical filtration system?
I have 2 skimmers both are HOB (BakPak and RemoraC Aqua Pro) no other mechanical or chemical filtration.

What is your biological filter?
100lbs of LR and 1" of live sand

How old is your aquarium?
Going on 3 years (no fatalities yet)

What kind and thickness of substrate do you have? Describe your system.
1" Live sand (thinking of adding more). 100lbs LR, 2 skimmers.

When did your aquarium first get set up and when did it cycle?
almost 3 years ago (another LFS told me to cycle with damsels...I now know better).

Do you have live rock in the aquarium? How many pounds of it is there?
Yes, 100lbs.
Do you have a sump; a refugium?
Nope. Planning on getting a sump.

Is your aquarium a reef aquarium or a FO aquarium?
FOWLR

I need to know the actual measurements and numbers for the following:
temp (and what range it usually stays within)
78 degrees

specific gravity
1.023
pH (tell me how you measured this)
8.3 I use Aqua Pharm.

ammonia (tell me how you measured this)
0ppm Aqua Pharm

nitrite (tell me how you measured this)
0ppm Aqua Pharm

nitrate
40ppm Aqua Pharm

Are you adding anything other than food into the aquarium?
No, just food mentioned in original post

Other than this fish, what other marine life have you added during the past 6 weeks?
10 more pounds of LR about 1 week before (cured for 4 weeks before adding to tank).

Have you done any maintenance or changed any equipment lately?
I do 25% water change every other week. Water changed 3 days before adding the fish.

Again, thanks for your help! Again, the fish will eat IF some food floats by it, but it will not actively go after the food.

[leebca]

The information is very helpful. Thanks.

The highest likelihood is that the fish is having acclimation problems. This doesn't mean you didn't acclimate it properly -- it could mean this though, or it could mean the fish has 'had it' with changes.

It is too early for a space stress issue, although with those two Tangs in that aquarium, you should expect space stressors to develop soon.

I would still recommend the large water change. Not so much for a water quality issue, but as a 'shock therapy.' A large water change can shift the fish's disposition and acclimation mode.

The fact that the fish is not coming forward and eating much may mean it has a fear of something. Yellow Tangs that are well adjusted often tend to boss around other fish. Is this or any other fish or invert bothering the Naso? Is the tank in a place where there is a lot of human traffic or something going on outside the aquarium? Are you using bright lighting? Did you dim the lights the day after adding the fish? You might consider dimming the lights for the next few days. You want to think of things you can do to make the fish feel safe and unthreatened.

You may also try to spend an hour just sitting in front of the aquarium. Once the fish becomes used to you, see what it is doing and what other fish are doing in relation to the Naso.

After you've considered and eliminated the above and done the water change, it may be just a matter of some additional time for the fish to finalize its adjustment.

Please keep us informed.

[joecon]

Thanks for the quick response!!!

I know tangs tend to not like each other, so I closely monitored how the yellow acts towards the naso for a few hours the first day. After a quick introduction/welcome from the yellow (yellow rubbed against the naso briefly, assuming it used its "razors" to establish he is the boss) it pretty much just left it alone. The other fishes ignore the Naso. I spend at least 2 hours in front of the tank after work (been doing this for almost 3 years as a way to unwind). I see zero aggression by any of the fishes.

I introduced the fish in the evening with lights off and the lights remained off until close to 24 hours later. There is very light traffic around the tank and the naso is used to seeing me as the source of food, she doesn't appear threatened by my presence.

I will follow your advice and do a large water change soon and see what happens.

I will keep you posted!!!

Thanks!

[leebca]

While waiting for an update joecon I want to take this opportunity to say that I am impressed with the way you take care of your marine system. Your time, effort and attention is to be congratulated. Few in this hobby devote so much towards treating their fishes with consideration.

[joecon]

Leebca,

Thanks for the kind words. I was born and grew up in Maui and have first hand seen many of the fishes sold at the LFS in their natural environment. To be honest, it makes me sad to see them in tanks, but by me not buying them will NOT stop the industry from catching and selling them. I never had a fish tank until I moved to California, again simply because I got to enjoy them in their natural environment...I lived near Kapalua beach and snorkeling for me was almost a daily thing (like jogging for some in the mainland).

So what I try to do is "rescue" the ones I can and put them in a tank in which I try to provide them with the best quality of life I can. I feel bad for fishes bought by people who buy them just because salt water tanks are "cool."

By the way, my naso is now eating and all I did was.......nothing You're right, it just needed time to get more comfortable!