Fish are dying one by one.


Quick background: fairly recently I've taken over this aquarium from someone second hand. Original post here. The equipment is outdated and it took me a while to figure out some of it wasn't working (pH meter and skimmer). Not to mention the water that came with the tank had way high No3. Meanwhile I managed to get pH under control (stable at 8,3 at the moment), salinity around 34 and the (new) skimmer is actually doing it's job. No3 is down by a lot, but still not good. Sadly enough, the process of getting here has cost me 2 clown fish and an angel. Left are: yellow tang, triggerfish and dwarf angel.

When I made my last update in the original post, things were looking up, but since then the trigger's color faded big time. And since just today his fins are a total mess!


Sorry for the reflection, worst time of the day to take a picture. Would anyone know what disease or parasite this is?
He lodged himself between the window and a part of a filter by the way. Usually he does that between rocks, but since yesterday evening he's doing it there instead. Yesterday evening he did not have any fin damage yet, he swam around, hunted some food but went back to the same spot after. When I woke up this morning he is again in this spot, but his fins all of a sudden started to look like this. Over the course of the day it has gotten worse quickly.

I'm very inexperienced when it comes to salt water fish diseases, could it be Brooklynella? Honestly at first I thought the other fish died from the bad water quality, the related stress and damaging themselves against the rocks. Obviously the related stress made them more vulnerable to parasites (or disease), which in retrospec I should have known faster. Seeing the yellow tang and dwarf angel look super good now, while the trigger has taken a turn for the worst, it's clear to me something is doing the rounds .. something that probably took down the clowns and the other angel.
I drove to the nearest fish store that still deals in salt water fish, they only had one medicine: colombo femsal. What is supposedly reef safe, meaning it's probably not strong enough for a severe case, but it is "all purpose treatment". Seeing there are no other fish store nearby, I reckon I can only proceed with this and hope it has effect. Meanwhile, I can order something online, which will probably take 2-3 days to get here at least. Assuming I can find out what it is.

When I got back home, the triggerfish released itself from it's holding position and launched itself like a rocket towards the other side of the tank. I've never seen him swim that fast. He bumped against the window, then launched itself again in the other direction but slower. He went back to one of his resting spots. Close up:

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His coloration is very white/dull compared to normal and you can see chunks of his fins missing.

Edit: I was thinking of using this colombo femsal in the main tank, I don't have any other options really. There is also no way I can catch the yellow tang and dwarf angel, unless I remove the rocks and drop the water level. Maybe I could catch the trigger if it relocates again to the upper position. It would be ideal if I can order a stronger medicine online and put the trigger in quarantine, but this will take a while to setup. The other fish have no symptoms as far as I can tell. Or not yet.
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Do you know if the previous owner used a quarantine process for all new fishes?

Your aquarium (and the fishes) have been through many changes. Fishes don't like change. Even when the water quality was 'bad' the fish were used to that. Making the water quality 'better' can pose a stress on the fishes. It's kinda no win situation, unless the changes are done very slowly over a long period of time.

I can see the tattered fins in both photos you've provided, but I'd prefer to see a close up video of the fish moving around. You can take a 1+ minute video under white lights and upload it to YouTube. Then you can post a link to the video here.

I can't make a clear diagnosis without seeing a video of the fish moving around. The usual cause of tattered fins is fighting with tankmates or a tankmate that nips at the fish. Even the 'bully fish' can suffer retaliation from the bullied fish. The next most common cause of tattered fins is water quality. Third is also fish health/nutrition. Hopefully you will find some time to read through the Fish Nutrition post. And last, but not least is a bacterial infection. This 'list' of possible problems are not in any particular order.

Are the fishes eating? Is the Triggerfish eating? I'm sorry that you may have limited access to the fish antibiotics like we have here in the USA. Take a look at the fish Medicine Cabinet post to determine what antibiotics you might have available. I'm unable to find the ingredients in Colombo Femsal. What does it say on the package for ingredients?

I'd recommend an antibiotic treatment for the Triggerfish in a quarantine/hospital tank.

In the UK (and maybe other parts of Europe) I think there is available:
  • Avloclor (chloroquine phosphate) can be obtained via prescription, and treats ich, velvet, Brooklynella, and uronema. Dosage is 10mg per 1L of saltwater.
  • Seachem Cupramine (ionic copper) treats ich and velvet. Therapeutic dosage is 0.5ppm, but this must be reached slowly and should be checked frequently.
  • Copper Power (chelated copper) treats ich and velvet. Therapeutic dosage is 2.0-2.5ppm.
  • Waterlife Myxazin (acriflavine, malachite green and formaldehyde) is used to fight bacterial infections. Often used to increase the effectiveness of a freshwater dip; dosage is 0.5mL per 3L of dip water.
  • NT Labs Acriflavin (acriflavine) is used as a 90min bath treatment for Brooklynella (similar to Ruby Reef Rally). Dosage is 7.5mL per 1L of saltwater.
  • Sera Tremazol (praziquantel) treats flukes and worms. Used as a 6 hour bath treatment at a dosage of 1mL per 11L of saltwater.
  • An alternative to Tramazol is Fluke Solve (praziquantel), which is dosed directly into a reef or QT vs. being used as a bath treatment. Dosage is 1g per 250L (55g) of saltwater.
I'm not sure if any of the above are available to you. I would suggest you obtain Avloclor and Tremazol, then also followed up by obtaining Copper Power.

The amount of space can be an issue, too. I'd say this group of fishes are a bit too much for that size of aquarium. Space stress can increase aggressions.

Sorry I can't offer anything specific at this time other than treating the fish with a fish antibiotic in a quarantine tank and feeding the fish with the proper foods.
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Thx for the replies. The guy I got the fish from probably had no quarantine procedure as he barely had time to take care of them.
I'll see if I can snap a video of him swimming, but he hasn't moved from the spot in the picture since.
Found a store that sells Seachem Cupramine and another that sells Sera Tremazol. Reading the posts you send and looking for other stores, but I'm having a hard time finding any local fish store that sells anything besides the 'cure all' stuff I have now. Honestly it's depressing. My only options are online from neighboring countries.
I'm sorry but he's not moving at all. Didn't come out for food either: trigger.
The only one I managed to film a little is the yellow tang, but he was very suspicious of me holding up my phone so he didn't want to come out much either. Since this evening the blue dwarf angelfish is hiding as well. He doesn't look particularly bad, but he was a lot more active before. He's in a dark spot I can't film.

Edit: another clip of the yellow tang. Like you can see ... no one else is coming out. Neither the trigger nor the blue dwarf angel.
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The Yellow Tang looks to be okay.

Canadians have difficulty acquiring fish antibiotics, too. Some just order them online and hope they make it through Customs. Copper Power is the best choice for a copper treatment, IMHO. The chelated copper works well and is safer.
I have some frozen food, all sorts,
green flakes and also big algea leaves for the tang,
and some very small pellet like food that sinks, I used to toss these on one of the plateaus, the trigger loved to pick those up, but he hasn't eaten anything since yesterday.

For feeding, I like rotated the different foods every day, trying not to feed to much either. But yea, right now no one is eating besides the tang.
A properly fed/nourished fish can live weeks without eating. Sometime near the end, they start 'eating' their own organs. At that point they are moribund.
big algea leaves
Not sure what these are. Is it nori? or seaweed?
Seaweed ye. I´ve ordered a bunch of the medicine that I could find, setting up a smaller tank in case I can catch the trigger once it arrives.
The medicine should arrive tomorrow. To be honest it will probably be too late by then. This afternoon I noticed the yellow tang taking little nibs at the trigger fish. The trigger wasn't even responding to it. His eyes also look blurry now. I saw no other option then moving him to a breeding box inside the main tank. It's very near the main return so he still has plenty of flow and I put the cleaning magnet on top so he has something to lodge himself in place, like he did in the picture. Normally he would freak out for sure, but he's just staying in place. He's breathing but that's about it. Not a good sign.


Meanwhile I prepared osmo water yesterday, mixed it with salt over the course of today and put it in a separate tank.


It has a heater, airstone and pump.
- Should I move him here as soon as the temperature is ok, or wait for the medicine?
- Is it ok to put filter cotton wool in the pump? Currently it's empty (and was cleaned out entirely)
I'll probably move the magnet here as well so he can use it again. In retrospec I probably shouldn't have put in so much water. It's exactly 40 liters (or 10 gallons).

Meanwhile I found the little blue guy, see video. He has some fin damage/rot as well. Did not come out for food at all and is just staying in that little cave. He's still quick as hell though, can't catch him for sure unless I break down the entire thing.

The yellow tang for some reason hasn't looked better since I got it. Feeding it in this video. Hoping he's strong enough and doesn't catch whatever the other guys all seem to have.
Should I move him here as soon as the temperature is ok, or wait for the medicine?
Depends. Is the biological filter working? I start a new quarantine/hospital tank by adding the nitrifying bacteria (I buy it online, many different sources/brands). I then drop in a few drops of ammonium chloride solution to 'feed' the nitrifying bacteria. When the ammonia level reads "0.0" it is ready for a fish. If the biological filter is working, then move the fish into the hospital tank when you can.
Is it ok to put filter cotton wool in the pump? Currently it's empty (and was cleaned out entirely)
Sorry. I don't understand what this means. The filter has media in it for the nitrifying bacteria, right? Adding cotton to a filter with media is okay.
The "blue tang' isn't looking very good. When the fish faces into the water flow it usually means there is a gill problem.

Feed the Yellow Tang as much as it will eat.

Hope this all works out. (y)
The blue one disappeared the day after I posted the clip. Looked for him everyday and only just found him. Dead of course.

I Moved the trigger to the separate tank the day after my post as well, he swam around a bit, then settled under the magnet. Honestly he looked dead already. The medicine arrived in the late afternoon and I dosed it per the instruction. Sadly enough it was to little to late, found him dead this morning.

The yellow tang is ironicly enjoying his new found peace. He´s swimming around a lot. Eating aggresivly from the seaweed sheets and looks good.

Now what do I do to ensure my last fish stays that way. I know there is something bad in there. One of the things I bought is esha minaroll vitamines to strengthen ur fish after disease. Dose this in the main tank?

Note that the yellow tang was scratching itself weeks ago, but is no longer doing that. Should I just monitor and hope his resistance is strong enough, or take other measures?
Video of the tang making his round to eat algea on the buttom corner. He´s also eating algea on the plateau above, but didnt catch that in the video. Don´t know how fast his breathing is supposed to be.
esha minaroll vitamines
I am unable to find exactly what this product contains and in what quantities. Speaking in generalities -- adding vitamins to the tank water just feeds the bacteria and doesn't help the fish.
how fast his breathing
The average ornamental marine fish should breath about 120/min or less. This fish, the Yellow Tang, is breathing about 200/min.
The medicine arrived
What medicine do you now have?
Should I just monitor
For now, yes. Clean out the hospital tank and 'sterilize' it. Use no soap. Wash (clean sponge or rag, scrubbing surfaces) with tap water first -- the whole system (filter, cover, heater, tank, etc.). Now 'wash" with bleach. I'm assuming that store bought bleach is available, containing 5% sodium hypochlorite, no fragrance and no dyes/coloration. Put one cup (237ml) in a gallon of tap water. Wear gloves and be aware that the solution will bleach colored clothing. Wash all surfaces again, including filter. Then thoroughly rinse everything in tap water. Finally rinse thoroughly again in RODI water or distilled water. Now it is sterilized. Set the hospital tank up again and start the biological filter. Get it ready for the Yellow Tang, if necessary.
If the Yellow Tang exhibits any out-of-the ordinary symptoms or behavioral issues, please let me know. What equipment do you have to measure water salinity?. The Instant Ocean Hydrometer is good, so long as you are aware that bubbles can interfere with a good reading. A floating hydrometer is good, but delicate (can easily break). You want any hydrometer that has small increments.
I've got a refractometer, some sort of copper threatment, a copper test, anti-parasite medicine (2 kinds) and anti-bacterial infection medicine. And lastly one to mix in the food to strengthen the fish after illness. Am still considering using that on the tang.

As far as I can tell, the tang is doing ok though. His breathing is sometimes slower than in the video, but still fast. I've been looking up some yellow tang videos, and some breath slower, some faster. I also visited the aquarium store again: compared to the fish there, my tang is not breathing fast at all. Not that it seems a good reference, if anything it makes me think the fish at the store aren't doing so well.

Now that the trigger is gone, I did bring in two cleaner shrimp. They molted in the quarantine tank on day one, so I kinda moved them to the main tank a few days later. After the first day in there, the yellow tang kept requesting to be cleaned. Eventually this happened: video. I don't have footage of the actual cleaning, but it seriously looked like the shrimp told the fish "follow me into my car wash". The tang got a thorough cleaning inside the cave. They've been cleaning him whenever requested ever since. The shrimps are doing really well, walking around a lot around dusk.

Not sure if it will make a huge difference, but I read cleaner shrimp are pretty good at pest control. Either way, they are now the only 3 occupants of the tank. The tang seems to be stress free, grazing like a cow all day long. Only freaks out whenever it is feeding time ... dashing like mad to grab every last bit of it. Don't know if that can be considered normal ...