Mysterious anthias deaths

[vetteguy53081]

I did not notice any uptick in aggression. They had a well established pecking order but no vicious chasing or nipping was observed.

You guys do have me wondering about diet/nutrition and about a curious anthias behavior during feeding time. Anyone that keeps anthias and feeds their tanks heavily probably knows what I'm talking about. Anthias are voracious feeders and will quickly gobble up as much food as they can. BUT, when there is plenty of food, they have a tendency to get greedy and end up spitting out all the food they just ate. This usually occurs after all the other food has been eaten and so the spit out food is quickly eaten (at least in my tank) by the gluttonous tangs and butterflies. Maybe heavy feedings are resulting in less food in the stomachs of anthias? Just spit-balling here.

You are on track and yes, they go bezerk like sharks at the sight of blood. Mine squabble here and there but same- No damge, but male can sure stress out a female

 

[MnFish1]

If you look to a freshwater source - discus. What tends to happen is the weakest fish feeds less and less - and dies. Followed by the next weakest fish, etc etc etc. You have a nice large tank IMHO - you need a much larger number of anthers for a 'school'. Again IMHO - the dominant fish prevent the less dominant fish from feeding. Best of luck with the tank

 

[Jay Hemdal Verified Community Expert]

After a lot of searching, I found a few instances on other forums of people reporting the same type of experience as I am currently experiencing, but there was no cause identified. Hoping someone here on R2R can help.
Here's what's going on:
Shoal of 9 bimac anthias. 1 male, 8 females in an SPS dominate reef (500 gal). No other anthias species. No new fish added for at least 6 months. All fish go through a 6 week QT process which includes prazi and metro in the food for internal parasites. No aggression among or within species (aside from the typical anthias pecking order). Fed 3 times per day. I was even getting regular spawning events with the bimacs! A couple weeks ago I noticed the largest female acting very 'male'. Couldn't find the male. He was hiding deep in the rockwork. Didn't think too much of it at the time. Next day two more were in hiding. Next day 1 more. None of them never came back out. Ever! Just sat in the rocks until they died, which took a week or more (seemingly until they starved). No signs of disease or aggression (before or after entering hiding). They looked physically perfect even in hiding. No other species were affected. Today, two more in hiding.
What on earth is going on?!?
@Jay Hemdal

Whoa - I'm just not sure. Sound like you did everything right. I've had issues with anthias and sex changes - where they don't deal with things like they would in the wild, and perhaps hormones building up in the water cause females to turn male, despite there already being a dominant male in the tank. That can wreck havoc with the social dynamics. I see the same issue with discus (minus the sex changes) where the social dynamics get all messed up and fish start dying due to being stressed out due to aggression (even though no ripped fins are ever seen).

Jay

 

[Reeffraff]

Whoa - I'm just not sure. Sound like you did everything right. I've had issues with anthias and sex changes - where they don't deal with things like they would in the wild, and perhaps hormones building up in the water cause females to turn male, despite there already being a dominant male in the tank. That can wreck havoc with the social dynamics. I see the same issue with discus (minus the sex changes) where the social dynamics get all messed up and fish start dying due to being stressed out due to aggression (even though no ripped fins are ever seen).

Hi Jay,
These fish definitely have a complex social structure! The bimacs were introduced into the tank in two groups. The first group was added almost 2 years ago and contained the (at the time) young male. I added 5 more females about a year ago. One of the females was almost as big as the male. He definitely bullied that one hard and didn't let it out to eat. It died before I could manage to get it out of the tank. Up until recently, that was the only anthias loss I've had with these bimacs. The sudden loss of several individuals including the male is what makes it 'feel' like a disease issue, but they all appeared in peak condition before (and even after) going into hiding. Here's a photo of the male about a week before he went into hiding, never to return out into the open.
I'm curious about possibility of the hormone buildup in aquaria you mentioned. Have there been any studies on that? I assume running carbon would solve it, since it's an organic compound?

 

[Koty]

FWIW another issue is that you have a deep water species. I wander what are the long term effects of being exposed to very strong light (sps tank?) and shallow waters. For me this was one reason for choosing the Red Sea anthias

 

[lagatbezan]

I had the same experience with bimacs, lyretails and coopers. They all make it through qt with a breeze but never last long.
Had 9 bimacs that went through a full qt with copper, GC and several formalin baths. They were in a 10g qts with zero issues and aggression for 60 days. Once in the main display after a couple of months I started losing them one by one. They would stop feeding and just hide. Didn’t notice any aggression at all between them and they were all different sizes. The weird thing is that the larger ones would die first. I was left with the smallest one which also perished a couple of weeks latter. I feed extremely heavily a varied frozen and flake foods. Not sure why and microscope scrapes didn’t show anything either.
@Reeffraff did you treat with formalin? I’m thinking maybe that might be the cause of my failures with them?
Such a shame because they add so much life to the tank.

 

[Koty]

I would never use formalin (accept in my lab in a chemical hood) its a dangerous voletile carcinogen. You treat your fish wit formalin, chances are that you determined the future cause of death: cancer. The"good news" is that it all take a long time because this is how cancer works. Also I would guess that is a very painful procedure for the treated fish

 

[52728299]

I had the same experience with bimacs, lyretails and coopers. They all make it through qt with a breeze but never last long.
Had 9 bimacs that went through a full qt with copper, GC and several formalin baths. They were in a 10g qts with zero issues and aggression for 60 days. Once in the main display after a couple of months I started losing them one by one. They would stop feeding and just hide. Didn’t notice any aggression at all between them and they were all different sizes. The weird thing is that the larger ones would die first. I was left with the smallest one which also perished a couple of weeks latter. I feed extremely heavily a varied frozen and flake foods. Not sure why and microscope scrapes didn’t show anything either.
@Reeffraff did you treat with formalin? I’m thinking maybe that might be the cause of my failures with them?
Such a shame because they add so much life to the tank.

I have heard it takes about 2 months for a male to appear out of a group of females. So could also be linked to hormone issues? If multiple fish began the switch to male it would make sense the bigger fish would go first..

 

[Jay Hemdal Verified Community Expert]

Hi Jay,
These fish definitely have a complex social structure! The bimacs were introduced into the tank in two groups. The first group was added almost 2 years ago and contained the (at the time) young male. I added 5 more females about a year ago. One of the females was almost as big as the male. He definitely bullied that one hard and didn't let it out to eat. It died before I could manage to get it out of the tank. Up until recently, that was the only anthias loss I've had with these bimacs. The sudden loss of several individuals including the male is what makes it 'feel' like a disease issue, but they all appeared in peak condition before (and even after) going into hiding. Here's a photo of the male about a week before he went into hiding, never to return out into the open.
I'm curious about possibility of the hormone buildup in aquaria you mentioned. Have there been any studies on that? I assume running carbon would solve it, since it's an organic compound?

Well, a top male dying kind of changes things from being a social hierarchy issue. I'm not sure what else it could be though, nothing is striking a familiar chord with me.

Regarding hormones in the water - mostly what I know has been observed artifacts; the discus issues are common. Male bird wrasses often develop bumpy snouts that is presumed to be due to overloading of hormones. Genicanthus angels change color, and of course anthias switch back and forth male/female.

different types of carbons remove different compounds. Carbon can have other issues (like causing HLLE and removing elements that you want, like iodine).

Jay

 

[brwaldbaum]

Well, a top male dying kind of changes things from being a social hierarchy issue. I'm not sure what else it could be though, nothing is striking a familiar chord with me.

Regarding hormones in the water - mostly what I know has been observed artifacts; the discus issues are common. Male bird wrasses often develop bumpy snouts that is presumed to be due to overloading of hormones. Genicanthus angels change color, and of course anthias switch back and forth male/female.

different types of carbons remove different compounds. Carbon can have other issues (like causing HLLE and removing elements that you want, like iodine).

Jay

Is it possible the often-reported mysterious deaths of chromis and anthias are due to uronema?

 

[Jay Hemdal Verified Community Expert]

Is it possible the often-reported mysterious deaths of chromis and anthias are due to uronema?

Possibly, but in the vast majority of cases I've seen myself, and here, acute Uronema infections are only seen in fish within about 40 days of importation. If fact, I say "vast majority" but I have actually never seen Uronema in fish that have been in a tank more than two months.....

Jay

 

[Dinkins Aquatic Gardens Verified Sponsor]

We supplement with live copepods and amphipods. It's not a requirement, but it gives me the peace of mind to know that if I'm not feeding exactly enough, then my anthias will be able to hunt some live food and get by until the next feeding.

 

[Reeffraff]

Just wanted to give an update:
No additional fish have gone into hiding. Remaining fish look perfect and eat well. One big shock: The largest female has ALREADY made a COMPLETE transition into a male. It took less than a week after the male died! Based on this and info others provided, I think I can reasonably surmise what happened.
The male was likely nearing the end of his life. I bought him as a fully mature male which would likely put him between 2-4 yrs old when I added him and he lived an additional 2 years in my tank. That's basically the full life expectancy of a bimac anthias. An old, weakened male was likely no match for some of the large females (who were basically the same size and over 2 years old). What's really interesting to me is that there wasn't a large battle to unseat the male. He seemed to realize that his time as ruler of the tank was over and simply hid himself deep in the rockwork and stopped trying to eat. This is pretty fascinating behavior because I have a large number of fish and feed heavily, so even a fish that is being bullied could easily come out and grab enough food at feeding time in all the chaos without being noticed. The tank is also 10 ft long, so plenty of space to avoid a bully.
Similarly, some of the other females, who were perhaps seen as a threat by the largest female, also went into hiding (never to return). It's like these fish just accept that they will not be welcomed into the new male's harem and just give up on life!!! They don't get beaten up. No fin tears. Truly bizarre.
There does seem to be one female close to the size of the new male who doesn't want to just go quietly into the night. That female does get most of the new male's "attention". But again, it's not an aggressive attack. Just a rush forward followed by some gentle rubbing, nudging. Will be interesting to see what becomes of this relationship. My guess is that I end up losing yet another fish.
In summary, there is zero evidence of disease which was my initial gut feeling. There is also no strong support for this to be a dietary issue, but given anthias' reputation of high metabolism fish that need frequent, high quality foods, I can understand why this was mentioned. The fact I had no issues for 2 years with these fish and they were regularly spawning also suggests the diet is adequate. Everything seems to point to a disruption in the social dynamics of the harem and the very odd fall-on-your-sword behavior in this species of anthias. That part totally sucks, because it would appear that every time there is a changing of the guard, I'm going to lose over half the shoal. I wish these fish weren't so darn gorgeous!