What is my Rock Beauty Angel doing?

SDguy · Sep 22, 2020

I've had my Rock Beauty since 2012. He (? pretty big gill spine for his size) is around 5.5". Two questions:

1. Why does his face turn dark sometimes? I can't tell if it happens only after feeding, or only in the evening, or if the combination of both is required. Does it signify anything? This has been going on for years.

2. Now I am not sure how long this next thing has been going on, but since recently installing a lot more lighting on the tank, I am able to get fancy with it, and have dawn, dusk, high noon, etc effects. During "dusk" he flares out all his fins, and swims around the surface of the water, his dorsal fin often breaking the surface. He doesn't look agitated or anything... if anything, he just kind of cruises around very "casually". Any ideas what this is about? I've included a video of this behavior below:

A sea K · Sep 22, 2020

He's probably just working on his tan. Sorry I have no idea but that is some interesting behavior.

SDguy · Sep 22, 2020

A sea K said:
He's probably just working on his tan. Sorry I have no idea but that is some interesting behavior.

He's late to the party then with only the blue T5's on ;Playful

Rincon_Reefer · Sep 22, 2020

I am not an expert, but I recently read an article about actinic lighting. The article pointed out that when you use settings on automatic aquarium lights where dusk or dawn are mimicked it can cause agitation in fish. This is because in nature the fish which are naturally diurnal are put on high alert during the transition phase from their daytime behavior into their night time hiding or resting state where they use natural defense mechanisms to avoid nocturnal predators. Kind of interesting, i wish I could find the link to the article. Maybe that is what is going on, since you said you got new lights.

SDguy · Sep 22, 2020

Rincon_Reefer said:
I am not an expert, but I recently read an article about actinic lighting. The article pointed out that when you use settings on automatic aquarium lights where dusk or dawn are mimicked it can cause agitation in fish. This is because in nature the fish which are naturally diurnal are put on high alert during the transition phase from their daytime behavior into their night time hiding or resting state where they use natural defense mechanisms to avoid nocturnal predators. Kind of interesting, i wish I could find the link to the article. Maybe that is what is going on, since you said you got new lights.

That sounds plausible. Although, other than the flared fins, his movements don't seem to indicate agitation. And I would think he'd be darting around the rocks.... not sort of floating around the surface. If you find the article please do share, sounds really interesting!

Maritimer · Sep 22, 2020

Angelfish spawn by rising toward the surface to dance with their mates in a "T" formation ... I'm wondering if s/he's looking for another rock-beauty of the opposite gender . . .

~B.

SDguy · Sep 23, 2020

Maritimer said:
Angelfish spawn by rising toward the surface to dance with their mates in a "T" formation ... I'm wondering if s/he's looking for another rock-beauty of the opposite gender . . .

~B.

Aww, now I feel guilty he's alone :/

ca1ore · Sep 24, 2020

That'd be my guess also. I have a pair of flame angles that do a mating 'dance' during the dusk period of my lighting. My RB does not, however ....

SDguy · Sep 24, 2020

Do fish give off any sort of pheromones, or similar? This seems to have started after having another Holocanthus in the system.

Maritimer · Sep 24, 2020

Fish absolutely use pheromones and chemical / scent signals to communicate. Adding another Holocanthus might have that effect - angels don't seem to be averse to hybridizing.

~B.

SDguy · Sep 24, 2020

Maritimer said:
Fish absolutely use pheromones and chemical / scent signals to communicate. Adding another Holocanthus might have that effect - angels don't seem to be averse to hybridizing.

~B.

They are rare, but there have been reports of Rock Beauty and Queen angel hybrids. I wonder if the tiny queen in my fuge may have caused all this.

SDguy · Oct 16, 2020

Another interesting observation. I am acclimating a pair of flame angels to the tank. The Rock Beauty apparently hates them, which is odd for a couple reasons. 1. He has never shown any aggression to any new addition, not even ones I thought would be an issue, like a small flagfin angel, for example. 2. I've housed him with a flame angel in the past without any issues.

Anyway, I can definitely add ticked off to the list of causes for the dark face

. You can see the difference when he's near the acclimation box vs when he is not.