Questions from an Observer

Good day! First of all, you should know that I am not a saltwater aquarium person. But, I still really enjoy watching them. In recent times, I have found myself stuck in a hospital with three gorgeous tanks. I have been watching them quite a lot. I noticed a couple of things with the fish that I was curious about but I had no one to ask. So, I decided to come here! One of the fish that is in all of the tanks is what I believe is a foxface rabbitfish. I noticed that they can seem to change from the yellow to a more brown color. Why is that? Does something with the light or his surroundings cause that? Also, all of the rabbitfish, in different tanks, have brown spots in the upper right corner of their bodies (if the face is on your left). When I tried to research this, it seemed like a bad thing, signaling worms or something. So, what do you think? Three different fish, three different tanks, the same brown spot.

The other fish I had noticed was a blue tang. When it would get close to lights out, which is at 8:09 pm, in case you were wondering, he would change his black lines to a more silvery and almost yellow color. His face would get pale, turning almost white. Then, he would turn back to his original colors. At first, I thought it was just the light hitting him at a certain angle. But then, he would turn and stay the same color. Any idea why he might do this? Any answers are appreciated. Thank you!

 

that is cool you have aquariums in the hospital. its good to have something productive while in the hospital, besides watching tv and hours of screen time...I might have some experience there.

 

Good day! First of all, you should know that I am not a saltwater aquarium person. But, I still really enjoy watching them. In recent times, I have found myself stuck in a hospital with three gorgeous tanks. I have been watching them quite a lot. I noticed a couple of things with the fish that I was curious about but I had no one to ask. So, I decided to come here! One of the fish that is in all of the tanks is what I believe is a foxface rabbitfish. I noticed that they can seem to change from the yellow to a more brown color. Why is that? Does something with the light or his surroundings cause that? Also, all of the rabbitfish, in different tanks, have brown spots in the upper right corner of their bodies (if the face is on your left). When I tried to research this, it seemed like a bad thing, signaling worms or something. So, what do you think? Three different fish, three different tanks, the same brown spot.

The other fish I had noticed was a blue tang. When it would get close to lights out, which is at 8:09 pm, in case you were wondering, he would change his black lines to a more silvery and almost yellow color. His face would get pale, turning almost white. Then, he would turn back to his original colors. At first, I thought it was just the light hitting him at a certain angle. But then, he would turn and stay the same color. Any idea why he might do this? Any answers are appreciated. Thank you!

Foxface change color based on mood (jet black when the lights are on= super stressed) and can change with various color intensity or patterns OR when they are going to rest for the night, they go to a sort of night camo color scheme as a natural defense from predators. Not sure if it could be parasite related in the ones you are observing, but it is also possible it's just their natural color scheme based on mood. I've had a One Spot Foxface in my tank for nearly 3 years and seen it do all sorts of things. They are a Spastic fish (ie easily spooked) by nature so their mood can change quickly.


For the Blue Tang it is the exact same as the Foxface, the bright colors would make them an easier target for predators in their natural environment so they go to a more muted color scheme to be harder to spot while they are resting.

 

that is cool you have aquariums in the hospital. its good to have something productive while in the hospital, besides watching tv and hours of screen time...I might have some experience there.

Yes, they are very therapeutic.

Foxface change color based on mood (jet black when the lights are on= super stressed) and can change with various color intensity or patterns OR when they are going to rest for the night, they go to a sort of night camo color scheme as a natural defense from predators. Not sure if it could be parasite related in the ones you are observing, but it is also possible it's just their natural color scheme based on mood. I've had a One Spot Foxface in my tank for nearly 3 years and seen it do all sorts of things. They are a Spastic fish (ie easily spooked) by nature so their mood can change quickly.


For the Blue Tang it is the exact same as the Foxface, the bright colors would make them an easier target for predators in their natural environment so they go to a more muted color scheme to be harder to spot while they are resting.

Ah, thank you! That makes a lot of sense. I also got to see one of the rabbitfish in the other tanks and his spots were different. They were larger, less circular, and asymmetrical. The one on his left was dark and large while the one on his right was dark in a small area and then light in the shape of the other. Something else I noticed today was in the sixth-floor fish tank (where I saw the other rabbitfish), there was a lot of hair algae. What do you do about that? Not that I can do anything. Just curious. I know in freshwater, you manually remove and then do more water changes. But in saltwater, you have all of the live rock (I think that’s what it is) to clean and some of the corals. It seems really difficult. And in that same tank, there was a yellow-tailed damselfish with spots on his fins and a white face. Is that ich? It looks kind of like it, but I know that you add salt to kill ich. Sorry for all of the questions, I have just had a LOT of time to look and I have not met the fish guy yet.

 

Yes, they are very therapeutic.


Ah, thank you! That makes a lot of sense. I also got to see one of the rabbitfish in the other tanks and his spots were different. They were larger, less circular, and asymmetrical. The one on his left was dark and large while the one on his right was dark in a small area and then light in the shape of the other. Something else I noticed today was in the sixth-floor fish tank (where I saw the other rabbitfish), there was a lot of hair algae. What do you do about that? Not that I can do anything. Just curious. I know in freshwater, you manually remove and then do more water changes. But in saltwater, you have all of the live rock (I think that’s what it is) to clean and some of the corals. It seems really difficult. And in that same tank, there was a yellow-tailed damselfish with spots on his fins and a white face. Is that ich? It looks kind of like it, but I know that you add salt to kill ich. Sorry for all of the questions, I have just had a LOT of time to look and I have not met the fish guy yet.

I ridded of my hair algae using snails. Also marine ich is different than fresh water ich thats why it can live in saltwater.

 

Yes, they are very therapeutic.


Ah, thank you! That makes a lot of sense. I also got to see one of the rabbitfish in the other tanks and his spots were different. They were larger, less circular, and asymmetrical. The one on his left was dark and large while the one on his right was dark in a small area and then light in the shape of the other. Something else I noticed today was in the sixth-floor fish tank (where I saw the other rabbitfish), there was a lot of hair algae. What do you do about that? Not that I can do anything. Just curious. I know in freshwater, you manually remove and then do more water changes. But in saltwater, you have all of the live rock (I think that’s what it is) to clean and some of the corals. It seems really difficult. And in that same tank, there was a yellow-tailed damselfish with spots on his fins and a white face. Is that ich? It looks kind of like it, but I know that you add salt to kill ich. Sorry for all of the questions, I have just had a LOT of time to look and I have not met the fish guy yet.

Hair algae is generally caused by one or more of the following: Overfeeding, Not Enough Clean Up Crew (as close as possible to 1 per gallon), Not enough filter floss/sock/cup changes (should be done every few days ideally), Running lights too long, Not enough water changes/nutrient export. If they addressed all of these then the GHA would likely disappear but chances are they aren't going to bother with it. As for the Damsel it is very possible it is marine ich (totally different than freshwater ich).

 

Some of the tanks seem like they are very well taken care of, but this one does not. I wonder if it is the same fish guy for all three tanks.

 

Tangs / surgeonfish often show different coloration sometimes because of stress (called stress lines) and at night especially. In my experience if rabbitfish are showing stress markings/lines during the day then there might be a water quality issue or tankmate issue.

Blue tangs are one of my favorites and they sometimes "play dead" when they are juveniles when they are super stressed. In the store tanks you can see this behavior in juvies as they try to lie flat under rocks and hide. Once they get bigger and get comfortable with their environment though they can be extremely active.

 

I generally agree with the post above, although I will say that Foxfaces can display different colors simply based on mood or being spooked during the day, so it could be that as well. My One Spot will periodically do this.