Clownfish and coral healthy, all other fish die

[betareef]

I have a small nano-tank. There is one small percula clown in it, some easy to keep coral (leathers, acans, star polyps) and some hermits, snails etc. He did have a couple of gobies in there (yellow and dartfish), but they died after a few months all doing well together. The yellow goby stopped eating and the dartfish was always skittish and I think also didn't eat well.

Now every other new fish I put in the tank dies within a week. Testing via a test strip shows everything normal - although my sg (float tester) did get to the high end of the acceptable scale for a while. I do weekly 10% water changes.

I caught some small fish test from the jetty (stripeys we call them). These are from the same water I use in my tank. Despite them eating OK for a few days, after a few more days, they all died off. No visible reasons - no spots or fungus or anything. I did notice a few of the them got a bit frantic and then hid under the coral at times. I even put a couple of common puffers (toadfish we call them) in there. They didn't eat well (unusual for a toadfish) and died after a few days as well.

The clownfish remains very healthy and is still eating well.

Could there be a toxin in the water than the clownfish is immune to? I did have some small jellyfish that came in with the water once. Could they have poisoned the water?

 

[FUNGI]

I would look at the clownfish as a candidate........territorial, especially in a small tank

 

[betareef]

I would look at the clownfish as a candidate........territorial, especially in a small tank

The toadfish was twice his size - and I have NEVER seen the clownfish chase the other fish, not once. Also, there was NO damage to the fish that died - no torn fins no scales missing.

 

[betareef]

Well, if noone else has any suggestions, I guess the clown has to go, followed by a complete water change.

Anyone want to suggest something to rescue the clown?

 

[Jay Hemdal]

I have a small nano-tank. There is one small percula clown in it, some easy to keep coral (leathers, acans, star polyps) and some hermits, snails etc. He did have a couple of gobies in there (yellow and dartfish), but they died after a few months all doing well together. The yellow goby stopped eating and the dartfish was always skittish and I think also didn't eat well.

Now every other new fish I put in the tank dies within a week. Testing via a test strip shows everything normal - although my sg (float tester) did get to the high end of the acceptable scale for a while. I do weekly 10% water changes.

I caught some small fish test from the jetty (stripeys we call them). These are from the same water I use in my tank. Despite them eating OK for a few days, after a few more days, they all died off. No visible reasons - no spots or fungus or anything. I did notice a few of the them got a bit frantic and then hid under the coral at times. I even put a couple of common puffers (toadfish we call them) in there. They didn't eat well (unusual for a toadfish) and died after a few days as well.

The clownfish remains very healthy and is still eating well.

Could there be a toxin in the water than the clownfish is immune to? I did have some small jellyfish that came in with the water once. Could they have poisoned the water?

There isn’t any toxin that would kill other fish, but leave the clown unscathed. Since the dying fish didn’t have fin damage, you can rule out aggression. It may be that the fish didn’t die from the same issue. If you want to take a deep dive, you can read this post and then post a full problem report over in the fish disease forum:

Some Helpful Hints When Posting or Responding to Threads in the Fish Disease Treatment and Diagnosis Section

Aquarium Fish Disease Problem Solving Determining the best course of action for a problem with your aquarium can be a difficult task. Even advanced aquarists will often need to seek the help of others for complicated or unique issues. Our intent here on Reef 2 Reef is to offer expert advice...

www.reef2reef.com

 

[Dom]

There isn’t any toxin that would kill other fish, but leave the clown unscathed. Since the dying fish didn’t have fin damage, you can rule out aggression. It may be that the fish didn’t die from the same issue. If you want to take a deep dive, you can read this post and then post a full problem report over in the fish disease forum:

Some Helpful Hints When Posting or Responding to Threads in the Fish Disease Treatment and Diagnosis Section

Aquarium Fish Disease Problem Solving Determining the best course of action for a problem with your aquarium can be a difficult task. Even advanced aquarists will often need to seek the help of others for complicated or unique issues. Our intent here on Reef 2 Reef is to offer expert advice...

www.reef2reef.com

My thought was that the clown has something it is passing along.

 

[Jay Hemdal]

My thought was that the clown has something it is passing along.

No - there isn’t any disease that a clownfish would carry and pass on to other fish, that wouldn’t make the clown sick as well.

 

[betareef]

There isn’t any toxin that would kill other fish, but leave the clown unscathed. Since the dying fish didn’t have fin damage, you can rule out aggression. It may be that the fish didn’t die from the same issue. If you want to take a deep dive, you can read this post and then post a full problem report over in the fish disease forum:

Some Helpful Hints When Posting or Responding to Threads in the Fish Disease Treatment and Diagnosis Section

Aquarium Fish Disease Problem Solving Determining the best course of action for a problem with your aquarium can be a difficult task. Even advanced aquarists will often need to seek the help of others for complicated or unique issues. Our intent here on Reef 2 Reef is to offer expert advice...

www.reef2reef.com

Aquarium Parameters:
Aquarium type: Reef
Aquarium water volume 55 litres
Filtration type Overhead trickle (tank built-in) spray bar fed by impeller pump with coral gravel and filter material in it
Lighting Inbuilt LED light
How long has the aquarium been established? 12 months - still have some algae problems
Leather in centre is undergoing it's periodical shedding so is closed up. Normall large and healthy looking.

Water quality (be sure to indicate what measurement units you are using, as well as the test kit brand)

Using Umlecoa Test Strips

Temperature 27 degrees C
pH: 8
Salinity / specific gravity 1.02
Ammonia 0
Nitrite 0
Nitrate 0
Phosphorus n/t
Copper 0
Other tests that have been done (if any)
Iron 0
Total Hardness GH 150
Total Alkalinity TA 180
Carbonate KH 180

In-depth information:
Have you lost any fish to this problem yet? (see below) Yes, at different times. Initially lost a yellow clown goby. Have also tried small dartfish goby, common goby, Stripey (Microcanthus strigatus), pufferfish (common toad)

The toadfish was added a week after the last stripey died. Captured wild and added to tank - lived 4 days only. Stripeys lasted similar time. Collected a few young stripeys (all very small) and the smallest ones died first.

Are any invertebrates affected? No, snails, hermits, all ok.
Coral unaffected as well.
Respiration rate of affected fish (in gill beats per minutes, count for 15 seconds and multiply by 4) Fish dead, so cannot measure
Are the affected fish still feeding? Stopped eating day or two before dieing
What remedies have you tried so far? Water changes
Digital image of the fish with the health issue, taken under white light - No pictures, but fish all looked undamaged with gills maybe flared a bit. No spots, no fungus.

 

[betareef]

Could it be stress? The tank is in a fairly exposed position and people walk past fairly often. Could this be enough to stress out a wild fish enough to die in less than a week?

 

[betareef]

There isn’t any toxin that would kill other fish, but leave the clown unscathed.

This is a bit of key information I was hoping to obtain. So, it isn't a toxin - good.

 

[betareef]

No - there isn’t any disease that a clownfish would carry and pass on to other fish, that wouldn’t make the clown sick as well.

Also good to know.

 

[Jay Hemdal]

Could it be stress? The tank is in a fairly exposed position and people walk past fairly often. Could this be enough to stress out a wild fish enough to die in less than a week?

Unlikely, fish in pet stores see a HUGE amount of foot traffic past their tanks. Fish are stressed by motion outside of their aquarium, especially when new from the ocean, but that stress is not "peracute" meaning it isn't normally fatal.

 

[Jay Hemdal]

Aquarium Parameters:
Aquarium type: Reef
Aquarium water volume 55 litres
Filtration type Overhead trickle (tank built-in) spray bar fed by impeller pump with coral gravel and filter material in it
Lighting Inbuilt LED light
How long has the aquarium been established? 12 months - still have some algae problems
Leather in centre is undergoing it's periodical shedding so is closed up. Normall large and healthy looking.

Water quality (be sure to indicate what measurement units you are using, as well as the test kit brand)

Using Umlecoa Test Strips

Temperature 27 degrees C
pH: 8
Salinity / specific gravity 1.02
Ammonia 0
Nitrite 0
Nitrate 0
Phosphorus n/t
Copper 0
Other tests that have been done (if any)
Iron 0
Total Hardness GH 150
Total Alkalinity TA 180
Carbonate KH 180

In-depth information:
Have you lost any fish to this problem yet? (see below) Yes, at different times. Initially lost a yellow clown goby. Have also tried small dartfish goby, common goby, Stripey (Microcanthus strigatus), pufferfish (common toad)

The toadfish was added a week after the last stripey died. Captured wild and added to tank - lived 4 days only. Stripeys lasted similar time. Collected a few young stripeys (all very small) and the smallest ones died first.

Are any invertebrates affected? No, snails, hermits, all ok.
Coral unaffected as well.
Respiration rate of affected fish (in gill beats per minutes, count for 15 seconds and multiply by 4) Fish dead, so cannot measure
Are the affected fish still feeding? Stopped eating day or two before dieing
What remedies have you tried so far? Water changes
Digital image of the fish with the health issue, taken under white light - No pictures, but fish all looked undamaged with gills maybe flared a bit. No spots, no fungus.

What is the tank's specific gravity? Is it really 1.02 or is there a number missing?

Does the tank have aeration (not just circulation)?

Wild caught puffers frequently bring disease into tanks if they are not treated first. However, that one seemed to have been one of the last fish tried?

The stripeys should have done fine, they are very hardy. Were they feeding well for you at first?

Yellow clown gobies are frequentl6y caught with cyanide and that can leave lasting damage, they can also be difficult to feed properly.

 

[betareef]

What is the tank's specific gravity? Is it really 1.02 or is there a number missing?

Does the tank have aeration (not just circulation)?

Wild caught puffers frequently bring disease into tanks if they are not treated first. However, that one seemed to have been one of the last fish tried?

The stripeys should have done fine, they are very hardy. Were they feeding well for you at first?

Yellow clown gobies are frequentl6y caught with cyanide and that can leave lasting damage, they can also be difficult to feed properly.

1.020 - bottom end of the acceptable range on the floatmeter.

The water passes through a spray bar (four separate sprays) into the filter. Plenty of aeration - never seen a fish in this tank hover near the surface as they will when short of air. The tank housed the clown and two gobies for the first 6 months or so - quite successfully.

Puffer was indeed the last.

Stripeys. Yes, they fed very well on the first days. Then the smallest ones died, and the bigger ones after that. These were young 5 to 10mm fish btw, not adults.

Yellow clown goby. Actually that could be correct. The yellow goby did die quite slowly, just lost interest in food it seemed. He was the first fish to die after some months of a happy healthy tank at the start. Maybe fair to exclude him from this current problem

 

[Mr. Mojo Rising]

low salinity, and a cheap salinity tool, so the salinity reading is probably wrong and unknown.

You have no rock in the tank so not much biofilter so the tank can't handle much livestock. Your tank is much too small for a puffer. The tank is too small and not enough filtration to handle 4-5 fish. Not enough rockwork for fish to hide.....

It looks like a low oxygen setting to me, low flow.

I'm sorry but I see a several things that should be corrected before adding any more livestock, the tank is not built properly to handle many fish or inverts.

 

[Jay Hemdal]

1.020 - bottom end of the acceptable range on the floatmeter.

The water passes through a spray bar (four separate sprays) into the filter. Plenty of aeration - never seen a fish in this tank hover near the surface as they will when short of air. The tank housed the clown and two gobies for the first 6 months or so - quite successfully.

Puffer was indeed the last.

Stripeys. Yes, they fed very well on the first days. Then the smallest ones died, and the bigger ones after that. These were young 5 to 10mm fish btw, not adults.

Yellow clown goby. Actually that could be correct. The yellow goby did die quite slowly, just lost interest in food it seemed. He was the first fish to die after some months of a happy healthy tank at the start. Maybe fair to exclude him from this current problem

I think for the corals, you ought to gradually raise the specific gravity to 1.023, but 1.020 is fine for fish.

Other than that, I can’t really diagnose this. My general advice is to not add new fish to any tank for at least 30 days after any fish loss due to unknown causes.

 

[Tamberav]

Sometimes stressed out fish won't eat so I suppose they could slowly die from that. That does not explain all the deaths but firefish are skiddish and they won't enjoy a tank set up like this. Rock work is not ideal. Salinity is not ideal. Test kits are not ideal. Flow looks less than ideal.

I would spend the $$ on better equiptment first. Thrive not just survive.

 

[betareef]

I think for the corals, you ought to gradually raise the specific gravity to 1.023, but 1.020 is fine for fish.

Other than that, I can’t really diagnose this. My general advice is to not add new fish to any tank for at least 30 days after any fish loss due to unknown causes.

Agree. 1.020 is the lowest it has been and I had intended slowly raising it. Had to honest in my report on test results though. Can't see it being the reason for the problems.

I agree that a "fallow" period of at east 30 days is in order. I would be happy if the tank just had one or two fish, except one clown doesn't quite look good. My current dilemma is if I should remove the clown, and really have no fish at all for a month or so, before trying something different. I have a feeling that's what I will do.

Maybe an invert and coral only tank?

 

[betareef]

Flow looks less than ideal.

I actually added an extra pump for flow (you can see it high on the rear of the tank, but that was mostly for the sake of the coral. The coral is doing well, except for the algae problems. The sinularia grew so large I had to prune to large pieces from it, and they are now growing well glued to a rock on the right hand side of the tank. The leather in the middle has nearly tripled in size. Even a small acan frag that nearly died from the algae is now opening up large and fat polyps.

Rock work is not ideal.

I would spend the $$ on better equiptment first.

I really can only have a small tank, and so the only thing I could do is add a bigger filter, (and some more rockwork). Obviously the lights are adequate for the coral I intend to keep. It has a heater. Not much else to spend money on?

 

[Tamberav]

I actually added an extra pump for flow (you can see it high on the rear of the tank, but that was mostly for the sake of the coral. The coral is doing well, except for the algae problems. The sinularia grew so large I had to prune to large pieces from it, and they are now growing well glued to a rock on the right hand side of the tank. The leather in the middle has nearly tripled in size. Even a small acan frag that nearly died from the algae is now opening up large and fat polyps.




I really can only have a small tank, and so the only thing I could do is add a bigger filter, (and some more rockwork). Obviously the lights are adequate for the coral I intend to keep. It has a heater. Not much else to spend money on?

Since flow is good, I would add some more rock/adequate hiding spots so fish feel comfortable.