Questions About Goldfish And Black Tetra

SO, I have a few questions.
Here's a little background; I have a fantail goldfish that is 8 years old, and a Black Tetra that is about the same age. My Tetra fish has been by itself for quite a period of time. You see, I was not taking care of them, my mother was. She did great these past years, but since I moved out I now have them to myself. Goldie (goldfish) is in my profile picture. The thing about Sharkfin (the Black Tetra) is that I've noticed he hides a lot. Which typically means that he's showing signs of being unhappy, and this type of fish generally travels in packs of 5-6 at minimum. So I'm wondering, should I get him friends? Or would that be too risky? I have another tank (10 gal) for quarantine if necessary. I'm just wondering if he would like it or not. He is old, but I don't want him to end his life unhappy. Will there be enough room? Considering my Goldfish is there too. Mind you Goldie has never tried to eat Sharkfin (They've been together for so long) so I don't think I need to worry about anything like that. My tank is 20 gallons.
ALSO, a question for Goldie. My mom fed him fish flakes and because of that he has developed what I strongly believe is Swim Bladder Disorder. (I have switched to Omega One sinking shrimp pellets) Because of the constant going to the top of the tank for food he took in quite a lot of air. My poor little fellow will occasionally float upside down, and has a hard time staying low. I can't find a good vet in Houston, Texas and I've heard about the Swim Bladder Treatment, which includes fasting the fish for 3 days and then feeding him skinned, defrosted peas. And with my Black Tetra being there (and completely healthy) I don't want to fast him! But Goldie eats up all the food every time. Any suggestions on how I should handle the Swim Bladder Disorder and the deal with fasting Goldie while Sharkfin is present? I really don't want to separate them but if necessary I'll figure out a means...
Thank you for reading! This is my very first post on fishlore.

*Update: WOW!! What awesome people! I am so happy & relieved for all of the help. Thank you all!!!!

 

Can you get a photo of the "black tetra" as I don't know of any black tetras that can live longer than 7 years. A healthy fish can last at least a week without food. When feeding its main food, pinch it and submerse it in tank water. Then feed it, this way, the food would sink instead of float.

 

That's what I have done; but I've just switched to sinking pellets all together. I still give the flakes (submerging them first though) just so they'll be able to lean off to the new food. I was using TetraFin goldfish flakes.
This is Sharkfin. I'm not positive he is a Black Tetra, but that is his closest match I've been able to find. He's not see-through.

Can you get a photo of the "black tetra" as I don't know of any black tetras that can live longer than 7 years. A healthy fish can last at least a week without food. When feeding its main food, pinch it and submerse it in tank water. Then feed it, this way, the food would sink instead of float.

Do you have any other advice involving my questions?

 

quick question what temp is your water at?

also when it comes to swim bladder the boiled De shelled peas is the way to go. You should be feeding boiled peas to your goldfish atleast 1-2 a week to avoid problem like these. I don't think it's necessary to wait 3 days , I would fast for 1 day and then feed the peas, and your tetra can eat the peas as well (just chop them small enough).

it is a black tetra very faded one.

also for your goldfish try getting some omega one goldfish pellets, before feeding soak them in a cup with aquarium water for 5-10 min then feed.

 

It looks like a blackskirt Tetra. His coloring is way off though. Has he always been that color?

chromedome52 Anders247 what kind of fish do you think this is?

I don't know what I would do. Your 20 gallon is big enough for 6 Tetra, but the goldfish and water temp could be an issue.

Your tetra can eat peas too. In fact he may love them. I agree with fasting for 24 hours then mash a boiled deshelled pea and feed them. It couldn't hurt at this point.

Edit: is your tank cycled? Do you have your water parameters handy? I'm thinking with fish you have kept alive for 7 years, your tank water is probably fine, but never hurts to check.

 

quick question what temp is your water at?

also when it comes to swim bladder the boiled De shelled peas is the way to go. You should be feeding boiled peas to your goldfish atleast 1-2 a week to avoid problem like these. I don't think it's necessary to wait 3 days , I would fast for 1 day and then feed the peas, and your tetra can eat the peas as well (just chop them small enough).

it is a black tetra

also for your goldfish try getting some omega one goldfish pellets, before feeding soak them in a cup with aquarium water for 5-10 min then feed.

Thank you sooooo much! My thermometer reads right below 79, but the heater is set to 75, (I feel like I should adjust it but I'm not sure) it's lowest setting being 68. (All degrees Fahrenheit)
Their tank before I switched them was at 80.
I just bought them a new tank, and let it cycle for 2 days.
I heard that I was supposed to wait a week at least but I checked the water (multiple times) and the new tanks water was actually cleaner than the tank they were originally in. They are both currently in it; it's been 3 hours and they're doing great, acting just as the had in the old tank. I went ahead and filled the new tank about 3 quarters way with purified water, and filled the rest with their original tank water then let it all filter. So I'm okay, right? I'm thinking about picking up some safestart just in case. I have lots of live plants in the tank. I checked the water (multiple times) and the new tanks water was actually cleaner than the tank they were originally in.
Goldie is of course eating up the live plants. He has fasted though and I do see improvement, I no longer find him chilling upside down in the tank! I'll go ahead and give them a little peas then. How many should he eat one or two? I'll cut up one for Sharkfin my Black Tetra.

It looks like a blackskirt Tetra. His coloring is way off though. Has he always been that color?

chromedome52 Anders247 what kind of fish do you think this is?

I don't know what I would do. Your 20 gallon is big enough for 6 Tetra, but the goldfish and water temp could be an issue.

Your tetra can eat peas too. In fact he may love them. I agree with fasting for 24 hours then mash a boiled deshelled pea and feed them. It couldn't hurt at this point.

Edit: is your tank cycled? Do you have your water parameters handy? I'm thinking with fish you have kept alive for 7 years, your tank water is probably fine, but never hurts to check.

Yes he has, he was darker when he was younger but that was years ago.
Thank you for your response! I just added another reply explaining what's up with my tank!

This is a photo of the new tank itself; with them inside. Goldie's been uprooting the Dwarf Anubias, of course. Is it okay if he eats it right now? Or should I remove it until I feed him peas? Looks like I have to remove it anyways and tie it down with some fishing line on some drift wood or something..

 

Ohhhhh ok. So this is making some sense now. New Tank. Did you throw away the old filter? Or is it the same filter you were using before? Because your filter is where all the good stuff lives. You want to keep that safe. If you threw away the filter pad then we are starting over.

Both fish need cooler temps. You need to lower your temp to 74-75. Go off of the thermometer, not the heater. Turn it down slowly. A degree every couple of hours. Watch your fish. See if they are doing ok with it.

Nitrogen cycle. This is where good bacteria eat the toxins in your tank. It lives on your filter pad/media. Not in your tank water. So by transferring the water, you didn't really do much. Just basically moved around dirty water. Although since you used purified water, it at least had some beneficial minerals in it.

Purified water? Not sure exactly what this is. Is it filtered tap water? Distilled water? Spring water?

Tap water has essential minerals in it to help keep your tank healthy. So even though you think bottled water is better, tap water is better in most cases in the long run. You will be ok for now. Just for future water changes, tap water is probably better.

Have you ever had your tank tested for Ammonia, nitrites, nitrates, & pH?

 

Welcome to the forum. I think I would just vary the diets and see how it goes. I have nothing to critique on your mother's fish keeping habits. If that tetra is really 8 years old she did just fine. I assure you many of us have never owned a Blackskirt that old. He is going to pass away someday and it probably won't be anyone's fault if you get through this cycle.

 

It is purified sink water. I have a filter underneath my sink. I DO have the old filter! It's too small to properly fit but I've added it to my current filter system since you've said that.

Welcome to the forum. I think I would just vary the diets and see how it goes. I have nothing to critique on your mother's fish keeping habits. If that tetra is really 8 years old she did just fine. I assure you many of us have never owned a Blackskirt that old. He is going to pass away someday and it probably won't be anyone's fault if you get through this cycle.

Thank you so much! I appreciate it deeply.

 

Was the old filter still wet? And after the cycle you can add a few more skirts if you like. Yes they are supposed to be in a larger group but Blackskirts will school in smallish nubers. There is a risk they will play a little rough though. Mine don't make contact often or cause harm but they do chase each other sometimes.

 

goldfish need water temp much much lower thriving at 68f-70f but for your tetra it's alittle cold I would have your temp at 74f.

do you have a apI test water master kit? checking parameters are very important.

do you know about the nitrogen cycle?

 

Was the old filter still wet?

Yes!

 

Welcome to the forum. I think I would just vary the diets and see how it goes. I have nothing to critique on your mother's fish keeping habits. If that tetra is really 8 years old she did just fine. I assure you many of us have never owned a Blackskirt that old. He is going to pass away someday and it probably won't be anyone's fault if you get through this cycle.

Right? It's such a long time! That coloring is usually the signal that something is up though. My skirts were almost totally black this morning and it was a nitrate spike (I think I have a dead snail somewhere). It wasn't even at 40ppm, but I did a big water change and everyone is back to their silvery stripey selves again. Guess I don't get to wait on water changes, ever. Sensitive little piranhas.

 

goldfish need water temp much much lower thriving at 68f-70f but for your tetra it's alittle cold I would have your temp at 74f.

do you have a apI test water master kit? checking parameters are very important.

do you know about the nitrogen cycle?

It's currently right below 79 according to my thermometer. I did not get the API master test kit, I used test strips (I know they're not as accurate) But I checked each tank 3 times and came up with same results for both every time. I can take another test and provide my readings.

 

It's currently right below 79 according to my thermometer. I did not get the API master test kit, I used test strips (I know they're not as accurate) But I checked each tank 3 times and came up with same results for both every time. I can take another test and provide my readings.

lower the temp slowly but surely In tell you hit 74f on your thermometer.

I don't personally trust test strip not ad accurate as you mentioned, but I'm still curious to see your readings if possible?

 

If i've had them for this long and they're still alive I'm not toooo worried. My mom had a very old set up for them; original everything, no heater, no thermometer, used tap water and didn't even bother checking the water. Cycling? What is that!! Yeah soo it's pretty much a miracle they've done so well taking into consideration their circumstances. But I suppose that's what they're used to now?

lower the temp slowly but surely In tell you hit 74f on tour thermometer.

I don't personally trust test strip not ad accurate as you mentioned, but I'm still curious to see your readings if possible?

Sure thing! Let me get my dog really quick and I will update with photos. Thank you for all of your help.

Thank you all! Best help I've gotten yet and I've been to a few pet/fish stores.

 

Right? It's such a long time! That coloring is usually the signal that something is up though. My skirts were almost totally black this morning and it was a nitrate spike (I think I have a dead snail somewhere). It wasn't even at 40ppm, but I did a big water change and everyone is back to their silvery stripey selves again. Guess I don't get to wait on water changes, ever. Sensitive little piranhas.

Now I thought they were healthiest when their black part is vibrant. Mine are silvery but active and seem happy. I guess I don't know for sure based on color Allie.

 

It is purified sink water. I have a filter underneath my sink. I DO have the old filter! It's too small to properly fit but I've added it to my current filter system since you've said that.

Does this mean you don't use a dechlorinator? Or does the purified water filter out Chlorine?

Was the old filter still wet? And after the cycle you can add a few more skirts if you like. Yes they are supposed to be in a larger group but Blackskirts will school in smallish nubers. There is a risk they will play a little rough though. Mine don't make contact often or cause harm but they do chase each other sometimes.

Yes!

Whew! That was a close one. You did the right thing. Just adding it to your new filter.

I would remove that plant if Goldie keeps trying to eat it. You don't want him to eat for a full 24 hours. Then feed the peas. Shark fin will probably eat like 1/2 a pea, but Goldie will probably eat 1 or 2 full ones. I mash mine, so the pieces are smaller. Some people put them on the end of a toothpick and feed them that way too. Have the fish come up and nibble on it.

Another remedy for swim bladder is Epsom salt baths. You will need a separate container. Goldie is pretty big, so something she can swim around in for 30-60 minutes. Depending on the size of the container will depend on the dose. I would certainly try the peas first though.

 

What brand strips do you have? I understand Tetra brand is decent and API strips are about worthless. I say that because I know somebody that has compared readings with API wet kit.

 

Now I thought they were healthiest when their black part is vibrant. Mine are silvery but active and seem happy. I guess I don't know for sure based on color Allie.

I think my color perception is off. I always focus on the opposite color that everyone else does lol

They had no silver showing at all. None. So they were stressed. Once I did the water change they went back to their normal color. Their black has always been pretty consistent. It's the silver I notice the changes with.

 

I think my color perception is off. I always focus on the opposite color that everyone else does lol

They had no silver showing at all. None. So they were stressed. Once I did the water change they went back to their normal color. Their black has always been pretty consistent. It's the silver I notice the changes with.

Yes I believe they should just have crisp black stripes. I gave a couple of mine to a buddy and he "fixed" them in about a week. His PH is 7.6, mine is 8.2+. Pretty sure I found their max preferred PH range and it is less than 8.2.

 

Yes I believe they should just have crisp black stripes. I gave a couple of mine to a buddy and he "fixed" them in about a week. His PH is 7.6, mine is 8.2+. Pretty sure I found their max preferred PH range and it is less than 8.2.

My pH is 7.6 haha

Alina the test strips will work for now, but you should look into getting at the very least an ammonia test kit. The strips don't test for Ammonia, and it is the most toxic to your fish so you will need to test for it. And in the future get the API Freshwater Master Test kit (liquid). With a large tank you will be glad you have it.

 

My pH is 7.6 haha

OK, so I will tell you the same thing I told him. It's the water so don't get too proud of your master fish keeping abilities or magic food lol.

 

New tank readings(first pic)
Previous tank readings; mind you this is the one they thrived in for so long. (second pic)

Does this mean you don't use a dechlorinator? Or does the purified water filter out Chlorine?





Whew! That was a close one. You did the right thing. Just adding it to your new filter.

I would remove that plant if Goldie keeps trying to eat it. You don't want him to eat for a full 24 hours. Then feed the peas. Shark fin will probably eat like 1/2 a pea, but Goldie will probably eat 1 or 2 full ones. I mash mine, so the pieces are smaller. Some people put them on the end of a toothpick and feed them that way too. Have the fish come up and nibble on it.

Another remedy for swim bladder is Epsom salt baths. You will need a separate container. Goldie is pretty big, so something she can swim around in for 30-60 minutes. Depending on the size of the container will depend on the dose. I would certainly try the peas first though.

Thank you!!! It does filter out chlorine.
Plant = removed! Thank you for the advice. And is Goldie a he or she??? I've always assumed "he" but it's not like the fish cares what pronouns they get!! lol Just wondering, how can you tell?

My pH is 7.6 haha

Alina the test strips will work for now, but you should look into getting at the very least an ammonia test kit. The strips don't test for Ammonia, and it is the most toxic to your fish so you will need to test for it. And in the future get the API Freshwater Master Test kit (liquid). With a large tank you will be glad you have it.

I will do so tomorrow! Do you suggest I use safestart or something of that sort?

Please let me know what you guys think of the readings. My nitrate levels were at 40 in my old tank, 20 in the new. The nitrite seems same for both? Caution? uh-oh. How should I go about solving that.. Total hardness is very hard for both. No chlorine in either. Alkalinity looks to be ideal, especially in new tank readings. and pH, I'm not really sure what reading that is. I will most definitely get the API MasterKit. Grabbed the strips because they were all I could pick up at the store at that moment. That's how my test strips looked for every test.

What brand strips do you have? I understand Tetra brand is decent and API strips are about worthless. I say that because I know somebody that has compared readings with API wet kit.

It is MarineLand 6 in 1 multi-test kit.

 

I don't know how to tell the gender of goldfish. Sorry. Shark fin is definitely a boy though lol

If you have a fish that is sick, Tetra Safe Start might not be the best. It recommends no water changes for 14 days and you might need to do one long before that. I would recommend using Seachem Stability or API QuickStart for bottled bacteria. And even if you don't need a dechlorinator, Seachem Prime is a great product. It does dechlorinate, but also protects against ammonia, nitrites, & nitrates. I highly recommend it.

 

I don't know how many test strips you have but you will potentially be using a lot of them. If your cut them in half from end to end they will work just the same. This could go as fast as a few days, or much longer depending on whether the old filter media primes the bacteria cultures.

 

I don't know how many test strips you have but you will potentially be using a lot of them. If your cut them in half from end to end they will work just the same. This could go as fast as a few days, or much longer depending on whether the old filter media primes the bacteria cultures.

I'll purchase whatever necessary. Getting the API Master Kit ASAP!

 

According to this article. Blackskirts will turn quite pale in color once they reach 5 years. So it looks like your guy's coloring is spot on for his age. That's so crazy he is so light in color. (I was looking for articles on blackskirt babies, since I have a very large female ready to burst lol)

 

According to this article. Blackskirts will turn quite pale in color once they reach 5 years. So it looks like your guy's coloring is spot on for his age. That's so crazy he is so light in color. (I was looking for articles on blackskirt babies, since I have a very large female ready to burst lol)

Wow that's so interesting! I've watched his color fade over the years so I assumed. & I saw your video!! Good luck with the little ones. <3

lower the temp slowly but surely In tell you hit 74f on your thermometer.

I don't personally trust test strip not ad accurate as you mentioned, but I'm still curious to see your readings if possible?

I have posted my readings, please let me know what you think.

According to this article. Blackskirts will turn quite pale in color once they reach 5 years. So it looks like your guy's coloring is spot on for his age. That's so crazy he is so light in color. (I was looking for articles on blackskirt babies, since I have a very large female ready to burst lol)

Also!! do you think I should get Sharkfin some friends? Or is he too old and that's just a giant risk? I want him to end his life happy as possible. He was purchased as a school but dwindled down to just him.

 

I'm not sure about adding friends or not. I'm undecided. I guess you could try. Maybe add 2 or 3 and see how it goes..

As far as your test strips. I think that you need to get Seachem Prime to help deal with your tank water while we get your cycle back on track. It will detoxify that nitrite you are seeing. I am sure there is Ammonia in there too. But because I see nitrates I know your nitrogen cycle is at least active. We just gotta get it back on track. Prime will help, so will bottled bacteria. Stability is the one I like, but API QuickStart is good too.

 

I'm not sure about adding friends or not. I'm undecided. I guess you could try. Maybe add 2 or 3 and see how it goes..

As far as your test strips. I think that you need to get Seachem Prime to help deal with your tank water while we get your cycle back on track. It will detoxify that nitrite you are seeing. I am sure there is Ammonia in there too. But because I see nitrates I know your nitrogen cycle is at least active. We just gotta get it back on track. Prime will help, so will bottled bacteria. Stability is the one I like, but API QuickStart is good too.

You are a LIFE!SAVER!!! Thank you so much I am beyond grateful for all of your wonderful advice. I will get everything tomorrow and post updates on how it's going! Thank you again.

 

Glad I could be of some help. Good luck. Let us know tomorrow how things look.

 

I'm shocked that no one has pointed this out yet - goldfish and black skirts do not belong in a tank together. Skirts are tropical fish and need 75-80f water, whereas goldfish are cold water fish and need 68-73f. Best thing to do would be to separate them - the vast amount of waste the goldie is producing in that small tank is polluting the water and probably irritating the poor tetra, but beyond that long term compatibility is an issue. I get that they have lived together for this long and have managed to survive, but it is far from ideal. The new tank is great for just the goldie (I love the tree by the way, very cool scape!) but in my opinion the skirt would be better off in the 10 gallon with 4-5 same species friends (though a bigger tank would be better, the 10 is better than where he is now). It's possible that because he is old and looks different they'll pick on him so you'd need to keep an eye on them, but chances are he'll be relieved and happy to have a school.

 

I'm shocked that no one has pointed this out yet - goldfish and black skirts do not belong in a tank together. Skirts are tropical fish and need 75-80f water, whereas goldfish are cold water fish and need 68-73f. Best thing to do would be to separate them - the vast amount of waste the goldie is producing in that small tank is polluting the water and probably irritating the poor tetra, but beyond that long term compatibility is an issue. I get that they have lived together for this long and have managed to survive, but it is far from ideal. The new tank is great for just the goldie (I love the tree by the way, very cool scape!) but in my opinion the skirt would be better off in the 10 gallon with 4-5 same species friends (though a bigger tank would be better, the 10 is better than where he is now). It's possible that because he is old and looks different they'll pick on him so you'd need to keep an eye on them, but chances are he'll be relieved and happy to have a school.

Thank you!!!!!!!!!!!!! Sooooo helpful. I will do that! For sure. I turned off the LED lights in the tank and it looks like Sharkfin (my tetra) is enjoying it now, he's out in the open and swimming about. So I will make everything perfect to his liking. Thank you very much!! <3

 

Always glad to be of assistance! I've taken in a few different schooling fish that had been kept alone for long periods - I had a glass catfish who lived in a community tank by himself for four years, and then almost a year in my tank before I finally found some friends for him, and it was so amazing and cute to watch them meet for the first time! He swam up to them, whiskered them a bit, and when he realized they were the same as him he did this crazy squiggly dance in the water in front of them, rubbed all up on them and then they were an inseparable school until he died of what I assume was old age. He was always very nervous when he was alone, he stayed in the same spot all day just swimming in place in the tallest plants in the tank and would only leave that spot at feeding time, and I knew he was nervous and out of his element but I never imagined I'd see such a drastic change in behavior when I added friends. It was about as heartwarming as fish things can be. That said, there is a small chance that Sharkfin won't like having company at all or will be totally indifferent, since he's been on his own for so long. I have only seen this happen once, but it's worth mentioning. I think he'll be thrilled and become the alpha male in no time since he's so big and the tank is his territory. If you can, get another 20 gallon for them - but if you can't, I do think the 10 gallon with a smaller group (5-6) is better than being with the goldie, as long as you keep up with maintenance.

I hope he loves whatever you decide to do, and both of your super old fish can live out the rest of their days in fishy bliss it's really amazing that they've lived together for so long - some fish are just so resilient, despite what we put them through when we didn't know better. My angels and pictus were put through absolute torture before I found this forum, and somehow they survived everything and are still with me. I hope they live to be as old as yours, and then some. Let us know what you end up doing and how it goes!

 

That's what I have done; but I've just switched to sinking pellets all together. I still give the flakes (submerging them first though) just so they'll be able to lean off to the new food. I was using TetraFin goldfish flakes.
This is Sharkfin. I'm not positive he is a Black Tetra, but that is his closest match I've been able to find. He's not see-through.


Do you have any other advice involving my questions?

Black skirt tetras are schooling fish and are very shy, which could explain the hiding. They also require higher temperatures than goldfish.

 

I'm shocked that no one has pointed this out yet - goldfish and black skirts do not belong in a tank together. Skirts are tropical fish and need 75-80f water, whereas goldfish are cold water fish and need 68-73f. Best thing to do would be to separate them - the vast amount of waste the goldie is producing in that small tank is polluting the water and probably irritating the poor tetra, but beyond that long term compatibility is an issue. I get that they have lived together for this long and have managed to survive, but it is far from ideal. The new tank is great for just the goldie (I love the tree by the way, very cool scape!) but in my opinion the skirt would be better off in the 10 gallon with 4-5 same species friends (though a bigger tank would be better, the 10 is better than where he is now). It's possible that because he is old and looks different they'll pick on him so you'd need to keep an eye on them, but chances are he'll be relieved and happy to have a school.

I sorta mentioned it as I said goldies require much much cooler water around 68f-70f and tetras need slightly warmer water

but in my opinion apenrently the OP stated that both fish are 8 years of age , lived togerher their whole lives and honestly at that point removing the tetra and adding friends might cause more problems then anything else sometimes fish well pick on the old or on the other side he might love it.

obviously it isn't an ideal situation cause I always say goldfish should be with goldfish and nothing else, and they shouldn't be at no temp higher then 72f , I've gotten into "arguments" on this forum with some people because of that , stating that higher temp is okay lol.


FOR THE OP
are you sure it's been 8 years cause a blackskirt lifespan is apparently 3-5 years?

 

I sorta mentioned it as I said goldies require much much cooler water around 68f-70f and tetra are tropical water,

but in my opinion apenrently the OP stated that both fish are 8 years of age , lived togerher their whole lives and honestly at that point removing the tetra and adding friends might cause more problems then anything else sometimes fish well pick on the old or on the other side he might love it.

obviously it isn't an ideal situation cause I always say goldfish should be with goldfish and nothing else, and they shouldn't be at no temp higher then 72f , I've gotten into "arguments" on this forum with some people because of that , stating that higher temp is okay lol.


FOR THE OP
are you sure it's been 8 years cause a blackskirt lifespan is apparently 3-5 years?

There's no need to argue about these things! That's the whole point of asking, because you don't know! Silly people lol. Thank you for your information! I'm pretty sure Sharkfin is 6-7 years. I had gotten Goldie in 2009 and Sharkfin happened *edit* apparently at the same time? Oh man I have no idea how old they are. I'm sorry I'm giving such different ages for my tetra! Apparently I had gotten him the same day as Goldie. Long story short, THEY'RE V OLD! lol
My tetra had friends but ended up being the remainder and has been with Goldie for 5 years. He had a tetra friend who was the same age but he passed from old age this year.
The temperature of their tank is slowly dwindling down, it's currently at 78 degrees Fahrenheit. They have never had their water temperature regulated before. I've literally been learning everything new since this Monday. A lot has changed - specially aquarium rules wise - since 2009. My mom wasn't able to spend a lot on them and upgrade their tank so poor Goldie was living in a 10 gal with Sharkfin all this time. I am taking into consideration the fact that Sharkfin is so old; I don't want to stress him out by introducing new younger fish. He seems to really like the new tank without the lights on, so I'm keeping them off until I find some that are dimmer.
Visiting the pet store soon, but luckily both of them have done wonderfully all night in the new tank! The old filter is helping quite a lot.

Black skirt tetras are schooling fish and are very shy, which could explain the hiding. They also require higher temperatures than goldfish.

Now that I have turned off the LED lights, Sharkfin (my little tetra) is loving the tank and swimming all about! I'm going to buy some much dimmer lights for them. I only had them on for an hour to see how it went, but Sharkfin isn't agreeing!

 

Silly people lol.

Love it!!

 

Always glad to be of assistance! I've taken in a few different schooling fish that had been kept alone for long periods - I had a glass catfish who lived in a community tank by himself for four years, and then almost a year in my tank before I finally found some friends for him, and it was so amazing and cute to watch them meet for the first time! He swam up to them, whiskered them a bit, and when he realized they were the same as him he did this crazy squiggly dance in the water in front of them, rubbed all up on them and then they were an inseparable school until he died of what I assume was old age. He was always very nervous when he was alone, he stayed in the same spot all day just swimming in place in the tallest plants in the tank and would only leave that spot at feeding time, and I knew he was nervous and out of his element but I never imagined I'd see such a drastic change in behavior when I added friends. It was about as heartwarming as fish things can be. That said, there is a small chance that Sharkfin won't like having company at all or will be totally indifferent, since he's been on his own for so long. I have only seen this happen once, but it's worth mentioning. I think he'll be thrilled and become the alpha male in no time since he's so big and the tank is his territory. If you can, get another 20 gallon for them - but if you can't, I do think the 10 gallon with a smaller group (5-6) is better than being with the goldie, as long as you keep up with maintenance.

I hope he loves whatever you decide to do, and both of your super old fish can live out the rest of their days in fishy bliss it's really amazing that they've lived together for so long - some fish are just so resilient, despite what we put them through when we didn't know better. My angels and pictus were put through absolute torture before I found this forum, and somehow they survived everything and are still with me. I hope they live to be as old as yours, and then some. Let us know what you end up doing and how it goes!

Wow!! That's so interesting! Thank you for sharing I highly appreciate it. Sharkfin had a buddy with him who was of the same age, his buddy was bigger than him though. Sadly he passed away about 5 months ago.. Probably from old age, he didn't show signs of being ill. Ever since I have turned off the LED lights in the tank Sharkfin is swimming all about! So I'm going to change the lights. But regarding the friends; I think I'm just going to move to my new house in less than a month, and go about switching him around that way. As for now they're doing good so I'm going to go with it and not stress them out with too much moving around. Luckily the first night in the new tank was a success! I am going to the pet store today to pick up an API master test kit and some solutions I was suggested in this forum. I'm thinking that i'm going to move my tetra into the 10 gallon tank with some new friends, but maybe after the move I can get another 20 gallon.. Hopefully!
They've lived so long I don't even know how old they are, which is absolutely crazy. I keep telling everyone the wrong dates (I apologize I was in elementary school when I picked them out) but luckily my mom remembers things!! I talked to her this morning asking her and she told me that I picked them out together the same day, so they're both equal in age. I know that they are for sure older than 7 years old, because they were there for me when my father passed in 2010, and had been there before that for about a year prior. I have drawings I made of them from 4th grade hahah! So yeah, they are very old!! I'm beyond relieved I have discovered such awesome, informative, fish loving people! I was having such a hard time deciding what to do with my underwater friends now that they're in my care, I was so stressed out and crying and freaking out; just a mess!! This has helped me SO much! They've been through heck of a situation considering nothing was ever regulated until now; but they are indeed mighty!!