Blue Tang in a 4ft?

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Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
Yes, it’s very similar to cichlids. I do the same thing with angelfish and it’s successful. The tomini could stay in the tank forever, and I would upgrade if you wanted to keep the hippa tang. 5 cm (2 inches) is a good starting size. Not to be mean but the convict tang looks to be on the thin side. What and how much/often do you feed? I would swap the gold rim though. That genus is aggressive anyways, but they’re even more so in smaller tanks.
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
Yes, it’s very similar to cichlids. I do the same thing with angelfish and it’s successful. The tomini could stay in the tank forever, and I would upgrade if you wanted to keep the hippa tang. 5 cm (2 inches) is a good starting size. Not to be mean but the convict tang looks to be on the thin side. What and how much/often do you feed? I would swap the gold rim though. That genus is aggressive anyways, but they’re even more so in smaller tanks.
The convict gets fed with all the other fish which is once a day. They’re fed ocean nutrition formula two (about half a cube) and he gets most of it tbh.
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
Yes, it’s very similar to cichlids. I do the same thing with angelfish and it’s successful. The tomini could stay in the tank forever, and I would upgrade if you wanted to keep the hippa tang. 5 cm (2 inches) is a good starting size. Not to be mean but the convict tang looks to be on the thin side. What and how much/often do you feed? I would swap the gold rim though. That genus is aggressive anyways, but they’re even more so in smaller tanks.
The convict gets fed with all the other fish which is once a day. They’re fed ocean nutrition formula two (about half a cube) and he gets most of it tbh.
I would add a half a sheet to a full sheet of nori to his diet every day. Tangs are predominantly herbivores and need nori to maintain their color and health. It will also probably help with aggression. Your other fish will like it too eventually. I’ve gotten almost everything from tangs, marine bettas, triggers, and groupers to eat nori. The only fish I’ve never gotten to eat it are eels, scorpionfish, and sharks lol. I like to see my tangs really thick and chunky. I think you’ll see a big difference in his behavior if you do that.
 
Hippo tangs can be territorial and there's no onsize fits all with any tang or fish in that matter. Its never a good idea to purchase fish in hopes to rehome later but people do it all the time. I have had to rehome fish due to size but I never got in the habit of purchasing just to rehome. The hippo tang was definitely a cool fish, immense deep color, cool swim pattern and if I glued a frag it felt like was in his way, he'd kindly remove it for me. Lol. If its blue that your looking for then you might be able find some nice substitutes that wouod last longer in ypur tank, a strakii damsel for one, very blue and colorful. Good luck on your choice🤙
 
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
You should fish that convict tang more. He does not look healthy!
 
You're always going to have those who say no tangs in anything less than a 1 million gallon tank...then there are those of us who have kept tangs healthy, fat, and happy for decades in all sorts of sizes of tanks. Yes a 4ft tank is plenty big for a hippo tang.
The reality is, it doesn't matter how big your aquarium is, it's a tiny tear drop compared to the ocean (even Polo reef at 17,000 gallons is nothing compared to the ocean). So, it's silly to get all hot and bothered over tank sizes and tangs. Obviously, you don't put a vlamingi in a 40 gallon breeder, so use common sense. The most important thing is that they are fat and healthy and able to swim freely without bumping into stuff just to turn around.
 
You're always going to have those who say no tangs in anything less than a 1 million gallon tank...then there are those of us who have kept tangs healthy, fat, and happy for decades in all sorts of sizes of tanks. Yes a 4ft tank is plenty big for a hippo tang.
The reality is, it doesn't matter how big your aquarium is, it's a tiny tear drop compared to the ocean (even Polo reef at 17,000 gallons is nothing compared to the ocean). So, it's silly to get all hot and bothered over tank sizes and tangs. Obviously, you don't put a vlamingi in a 40 gallon breeder, so use common sense. The most important thing is that they are fat and healthy and able to swim freely without bumping into stuff just to turn around.
i mean his tank is a 60 gallon so about 12" wide the fish gets 9" in captivity so i would say it would not be able to turn around or just barely
 
Sure, he'll have to upgrade that tank or sell the tang if he wants to keep it long term. But, for now, a baby blue tang would be fine. Most new people to the hobby don't keep tanks running longer than 1-2 years anyway before they upgrade or leave the hobby.
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
I am not a fan of planned removal after it gets too big, so I vote no.
 
A hippo tang is going to outgrow that tank in less than a year. Mine went from 3"-7" in a year and would bulldoze corals when it got spooked. I kept mine in a 4' 120gallon and it was way too small for it imo. More tangs will not lower aggression in a small tank.
 
Hey all,
I have a 4ft long 303 litre reef tank (including sump) and I have a pair of clownfish, a yellow coris wrasse, a flame hawkfish, a yellow coral goby, a convict tang, and a gold rim/white cheek tang.

My gold rim tang has become too aggressive and my mate (who has been in the hobby for over 10 years and a marine biologist) told me I should probably swap him for another fish, even though I did buy the gold rim off of him but it wasn’t aggressive back then. The gold rim has killed one of my wrasses and scopas tang so I agree that it’s time he goes.

Anyway, I was told by the same mate after I said how much I want a blue tang in the future when I have a bigger tank when I eventually move out, and he said that I can have one still since they have them at the shop I buy all my fish and corals from and they’re only about 3-5cm and he said I’d be able to have one in my tank for about a year and a half before needing to rehome it. Is this possible? Also would the blue tang be less aggressive than the gold rim? None of my other fish are aggressive (other than the female clown to her male partner for breeding) so without the gold rim will aggression be mostly fixed?

Thanks!
Tangs are inherently territorial. Space wise, you can keep a juvenile in that tank for that period of time. When you say blue tang, do you mean an Atlantic blue or a blue hippo. Atlantic blues are in the same genus as your gold rim, and can be aggressive, but they’re not as aggressive as gold rims or the powders. That entire genus is pretty mean though. Blue hippo tangs seem kind of dopey, and they’re pretty passive when they’re young. However, I’ve had them turn into total terrors when they get bigger. One of them was probably the meanest tang I’ve ever had besides a purple tang. The most even tempered tang I’ve had is a yellow tang. Each fish is different though. In a larger tank your tangs will be less aggressive since they have more space, and if you want more than one tang, I would do at least 3-4 to space out the aggression. If your lfs, does not qt, make sure to qt your hippa tang. They’re ich magnets.
Yeah it’s a hippo tang. So you’re saying if I do tangs to avoid having just the two and get a possible third and/or fourth? I used to have african cichlids so is it sort of like that where having more lowers aggression than having less? The convict is probably the most peaceful even more than my clowns and is still very small as he was caught out of a tidepool (he’s roughly 5cm, about the same size as the hippo tang I’m getting and I’ll attach a photo for size reference). Thanks for the input though! I’m probably going to swap the gold rim out for the hippo and if you reckon I should get an extra one or two for aggression I’ll maybe think about a bristletooth or tomini which will be able to stay in the tank full time.
20260221_142840_1352524D-9C71-4CCA-BB8F-7AFA7D5E93D8.png
Yes, it’s very similar to cichlids. I do the same thing with angelfish and it’s successful. The tomini could stay in the tank forever, and I would upgrade if you wanted to keep the hippa tang. 5 cm (2 inches) is a good starting size. Not to be mean but the convict tang looks to be on the thin side. What and how much/often do you feed? I would swap the gold rim though. That genus is aggressive anyways, but they’re even more so in smaller tanks.
The convict gets fed with all the other fish which is once a day. They’re fed ocean nutrition formula two (about half a cube) and he gets most of it tbh.
I would add a half a sheet to a full sheet of nori to his diet every day. Tangs are predominantly herbivores and need nori to maintain their color and health. It will also probably help with aggression. Your other fish will like it too eventually. I’ve gotten almost everything from tangs, marine bettas, triggers, and groupers to eat nori. The only fish I’ve never gotten to eat it are eels, scorpionfish, and sharks lol. I like to see my tangs really thick and chunky. I think you’ll see a big difference in his behavior if you do that.
I like the purple sea veggies but also feed the one with garlic extract to for the health benefits
 
then there are those of us who have kept tangs healthy, fat, and happy for decades in all sorts of sizes of tanks. Yes a 4ft tank is plenty big for a hippo tang.

Sure, he'll have to upgrade that tank or sell the tang if he wants to keep it long term.

Contradiction? Or attempted justifications of one’s own actions?
 
I haven’t kept a convict tang but don’t they become extremely aggressive? I also don’t like the “re-home” plan. The starckii is a great recommendation for that size tank. I loved mine. Always swimming.

6194.jpeg
 
I haven’t kept a convict tang but don’t they become extremely aggressive? I also don’t like the “re-home” plan. The starckii is a great recommendation for that size tank. I loved mine. Always swimming.

6194.jpeg
I have heard they do become really aggressive, never kept one.

But yes OP neither of those tangs should be in that tank, this is why you have aggression issues. When tangs are cramped they become aggressive. I vote no
 
I haven’t kept a convict tang but don’t they become extremely aggressive? I also don’t like the “re-home” plan. The starckii is a great recommendation for that size tank. I loved mine. Always swimming.

6194.jpeg
I have a Convict Tang and he is kept in check by my Yellow Tang. During the first 6 months my Conviction got cut by the YT 4 different times—the Convict healed but I was monitoring closing to see if I had to rehome. Thankfully the Convict settled in over time. The Convict is the most aggressive eater in the tank (will be the first to the nori clip every time) and defends his nighttime hiding spot at lights out aggressively.
 

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