Mysterious anthias deaths

[Reeffraff]

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

 

[albano]

Have no idea what’s going on, but after many attempts, I won’t even try another anthias in my tanks.

 

[Reeffraff]

Have no idea what’s going on, but after many attempts, I won’t even try another anthias in my tanks.

Did yours also just go into permanent hiding, or was it something else? What species? How long in the tank before they died? I'd love to try and find some commonality with other experiences to try and figure out what is going on.
I know uronema can be pretty devastating to anthias, but that disease leaves obvious sores on the fish and usually only affects new additions for some reason.

 

[vetteguy53081]

Pictures of any of the fish under white lighting would be very helpful.
Anthias other than occasionally fighting, they are susceptible to uronema disease as well as bacterial

 

[Reeffraff]

Pictures of any of the fish under white lighting would be very helpful.
Anthias other than occasionally fighting, they are susceptible to uronema disease as well as bacterial

Impossible to get any shots of the ones in hiding.
Here's one of the remaining females. Eats and behaves normally. The ones in hiding look the same.... until they die.

 

[Koty]

What are you feeding them? They need a lot of high quality food

 

[vetteguy53081]

Impossible to get any shots of the ones in hiding.
Here's one of the remaining females. Eats and behaves normally. The ones in hiding look the same.... until they die.

Do the other ones have any red sores on body, raggy fins, bloating ?
You can add an air stone to increase oxygen and some foods they should be gettng are:
LRS Reef Frenzy
mysis shrimp
Hikari marie cuisine
small plankton
chopped krill

While they will eat flakes and pellets, this is not a good diet for them

 

[Reeffraff]

What are you feeding them? They need a lot of high quality food

Mysis, PE mysis 2x per day. NLS pellets 1x. Also nori 1x per day (but that's obviously not for the anthias).

 

[KrisReef]

What you describe sounds like the alpha male was getting weak, so a challenger (a really mean one!) is taking out the competition. I'm not an anthias specialist but I do know a bit about biology and succession. This sounds like a loosing battle where you may end up with one male, and maybe 1-2 females if he lets them live?

 

[vetteguy53081]

Mysis, PE mysis 2x per day. NLS pellets 1x. Also nori 1x per day (but that's obviously not for the anthias).

Not an adequate diet. They need fats and aminos and foods mentioned will provide such. I have 6 anthias for almost 4 years

 

[Koty]

They are plankton eaters so I feed them fresh mussels and easy reef masstick (and three more feedings with dry Vitalis pellets/hikary krill pellets. I have them for 8 monthes and the bigger is starting to change color

 

[Reeffraff]

Do the other ones have any red sores on body, raggy fins, bloating ?
You can add an air stone to increase oxygen and some foods they should be gettng are:
LRS Reef Frenzy
mysis shrimp
Hikari marie cuisine
small plankton
chopped krill

While they will eat flakes and pellets, this is not a good diet for them

No ragged fins, sores or bloating/scales protruding. No body or fin discoloration. The ones in hiding don't appear any different than the ones actively swimming around. They get good quality foods several times per day. I would think if it was a nutrition issue, they wouldn't have been regularly spawning just before this event.

 

[vetteguy53081]

No ragged fins, sores or bloating/scales protruding. No body or fin discoloration. The ones in hiding don't appear any different than the ones actively swimming around. They get good quality foods several times per day. I would think if it was a nutrition issue, they wouldn't have been regularly spawning just before this event.

Not saying its a nutrition issue but diet inadequate. From what you describe, may be an aggression issue

 

[Koty]

I agree but spawning may have a draining effect vitaminewize

 

[Reeffraff]

Not an adequate diet. They need fats and aminos and foods mentioned will provide such. I have 6 anthias for almost 4 years

Curious about this. No doubt anthias are a high metabolism fish and need frequent high quality foods. What in mini mysis, PE mysis and NLS is not present in other foods? For example, PE mysis has the highest fatty acid profile of any natural food. Anthias eat mostly planktonic crustaceans in the wild (copepods, mysids etc).

 

[Reeffraff]

I agree but spawning may have a draining effect vitaminewize

I was wondering about this as well. Perhaps spawning was taking a physiological toll on them. I've had the male and several females for over 2 years though, and they've been spawning for over a year now. Seems odd it would just start taking a toll now. Also, males spend a lot less physiologically on reproduction than females. I would think the smaller females would have the toughest time, but size/sex doesn't seem to predict which ones go into hiding and why they never start eating again. This one has me scratching my head.

 

[Koty]

Any knolrdge about their life span?

 

[vetteguy53081]

Curious about this. No doubt anthias are a high metabolism fish and need frequent high quality foods. What in mini mysis, PE mysis and NLS is not present in other foods? For example, PE mysis has the highest fatty acid profile of any natural food. Anthias eat almost mostly planktonic crustaceans in the wild (copepods, mysids etc).

These fish are carnivores often seeking floating foods and in the wild are planktivores but in captivity carnivores and Omnivores. Due to their hyperactive traits, they need decent tank current to support good wyater quality.
Back to diet, reason they need aminos and vitamins is that they are susceptible to liver disease and uronema and this variety of food helps their immunity system.

 

[vetteguy53081]

Any knolrdge about their life span?

healthy specimens- Generally 5-6 years but also dependent on water quality, diet and low stress environment

 

[Reeffraff]

Not saying its a nutrition issue but diet inadequate. From what you describe, may be an aggression issue

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.