Half of my fish suddenly died.

[Dlewis0714]

Hello all this is my first post, and any light you can shed on this would be much appreciated. I setup a 36 gallon bowfront tank with live sand an about 40-45 pounds cured live rock. As soon as my tank was fully cycled I bought a Coral Beauty and a Carpenter Wrasse from my LFS. I also added 2 small baby clowns from a previous small tank that I had running. The carpenter wrasse was about 3" long very active when it was time to eat but mostly stayed under a rock where he made his home. The coral beauty was very active eating and picking at rocks throughout the day. This past Friday we woke up and the wrasse was on the bottom dead. The day before he was eating and swimming fine. I did a water test and everything looked good nitrate was around 20ppm ammonia 0-.025 nitrite 0 and ph 8.2. I checked the fish and didn't see any wounds or gouges. Left me scratching my head as the other 3 fish seemed perfect and water quality looked good. On Saturday I did a 30% water change. I used half RO water and half distilled water from the store with instant ocean. I retested the water everything still good the nitrate was down to about 10-15 or so and everything else the same the 3 fish are all happy and eating. Tuesday morning I wake up and the coral beauty is at the top of the water swimming vertically gasping for air. He died about 4 hours later. I took the fish along with my water to the LFS I bought them from to see if I could get an explanation. He did all the tests on the water and inspected the fish. The fish didn't look like it was sick at all and he said people would kill for the water in my tank. He said it was perfect. So I'm left scratching my head. My clowns are still thriving and happy and water still testing good. I would love to add some more fish to my tank but I'm a little scared right now because of this. I attached a picture of the tank with the wrasse the day before he died and my water test results.

 

[Crabs McJones]

Welcome to R2R! Sorry to hear about your fish If water parameters are coming up fine, some sort of parasite would be my guess. Whether its velvet, ich, flukes or internal parasites it's hard to say without a close up picture of the fish.

 

[melanotaenia]

Some other thoughts: any cleaning products near/around the tank lately? Any changes to routine/changes to equipment? If not, it may be worth having your water more thoroughly tested to see if something is getting in there that is affecting your fish

 

[BeejReef]

Is there any water movement in your tank aside from the hob filter? Can't tell from the pics.

 

[vetteguy53081]

Was tank new or used and was it cleaned prior to fill and how cleaned.
According to test results a couple of crucial levels are up here. How long has tank been running as it appears to be new and a few intros done what seems quickly.
I would highly suggest to take a water sample to a trusted LFS (pet store) and have them test water for you to both compare with your readings and see what results they come up with.
A water change may be in order as is no more stocking of fish for 2-4 weeks and go slowly from this point forward. Feed very sparingly also the first few weeks.

 

[Dlewis0714]

Welcome to R2R! Sorry to hear about your fish If water parameters are coming up fine, some sort of parasite would be my guess. Whether its velvet, ich, flukes or internal parasites it's hard to say without a close up picture of the fish.

I took the fish to the LFS and they said they didn't see any type of sickness. Eyes were bright colors vibrant.

 

[rsumner]

I'm going to second what @William DeCoursey is asking...I've never had this problem myself, but with you seeing the fish swimming at the top of the water, you could be oxygen deprived. I see an HOB filter and depending on where you keep the water levels, you may not be getting great gas exchange.

 

[Dlewis0714]

Was tank new or used and was it cleaned prior to fill and how cleaned.
According to test results a couple of crucial levels are up here. How long has tank been running as it appears to be new and a few intros done what seems quickly.
I would highly suggest to take a water sample to a trusted LFS (pet store) and have them test water for you to both compare with your readings and see what results they come up with.
A water change may be in order as is no more stocking of fish for 2-4 weeks and go slowly from this point forward. Feed very sparingly also the first few weeks.

The tank is at 16 weeks. What levels are high? I read the nitrate at 15-20ppm ammonia looks to be almost 0 nitrite 0 and ph 8.2. please explain the levels that are high because I'm told these are good levels for fish only aquarium. In my post I did explain that took the water and the dead fish to my lfs. The tank was brand new and I cleaned with RO water. My other 2 clowns are perfectly fine.

 

[Dlewis0714]

I'm going to second what @William DeCoursey is asking...I've never had this problem myself, but with you seeing the fish swimming at the top of the water, you could be oxygen deprived. I see an HOB filter and depending on where you keep the water levels, you may not be getting great gas exchange.

I have 2 30 gallon hob marineland filters with built in protein skimmers. I heard it's normal for the clowns to be at the top half of the tank. The coral beauty and wrasse stayed in the bottom of the tank 90% of time. I did raise the water level to the top after water change but the skimmers blow bubbles in there frequently. When the wrasse died the water level wasn't completely to the top but when coral beauty died they were.

 

[Dlewis0714]

I took the fish to the LFS and they said they didn't see any type of sickness. Eyes were bright colors vibrant.

Is there any water movement in your tank aside from the hob filter? Can't tell from the pics.

There's 2 hob marineland filters with built in protein skimmers.

 

[rsumner]

I have 2 30 gallon hob marineland filters with built in protein skimmers...

Hrmmm....sounds like you have gas exchange covered. Since "half your fish" only accounts for 2 fish, I wouldn't stress about it too much. As far as your Nitrate readings: with such a light bioload, it shouldn't be tough to maintain Nitrate well below 10ppm. I don't think you'll ever know for sure what caused the issue with those fish, but if I were in your position, I would get those Nitrates consistently below 10ppm to make me more comfortable before adding more lifestock. With 4 fish and no coral, you should have appropriate systems in place that should have been able to keep those in much better check. Again, this is probably not your silver bullet, but would be the one thing I would improve upon before I got new fish.

Lastly, if I lost two fish that I got from the same LFS, I would likely purchase my next fish elsewhere.

 

[homer1475]

This is a FOWLR system... 10 to 20, heck even 100ppm would be acceptable to a fish only system.

Nitrates are/were not your problem.

 

[Dlewis0714]

Hrmmm....sounds like you have gas exchange covered. Since "half your fish" only accounts for 2 fish, I wouldn't stress about it too much. As far as your Nitrate readings: with such a light bioload, it shouldn't be tough to maintain Nitrate well below 10ppm. I don't think you'll ever know for sure what caused the issue with those fish, but if I were in your position, I would get those Nitrates consistently below 10ppm to make me more comfortable before adding more lifestock. With 4 fish and no coral, you should have appropriate systems in place that should have been able to keep those in much better check. Again, this is probably not your silver bullet, but would be the one thing I would improve upon before I got new fish.

Lastly, if I lost two fish that I got from the same LFS, I would likely purchase my next fish elsewhere.

Thanks. I will do a 50% change this weekend and should achieve the nitrate goal. I didn't want to lower it too quickly and shock fish. I'm going to take your advice and switch lfs

 

[W1ngz]

I have 2 30 gallon hob marineland filters with built in protein skimmers.

What filters are these? Do you have a model name? I'd love a filter/skimmer combo unit for my quarantine tank, but never saw one before.

 

[Dlewis0714]

What filters are these? Do you have a model name? I'd love a filter/skimmer combo unit for my quarantine tank, but never saw one before.

It's a little noisy but I like it

 

[Paul B]

I say, Nope, Nope and Nope. This is a very easy diagnosis and I hate to diagnose from afar where I can't see how the fish died.
This is the problem and it is a problem many people don't think of.
When you "cycle" a tank, that just means the tank has enough bacteria in it to oxidize a frozen shrimp. goldfish, T Bone steak or whatever you used to cycle it with. There isn't any more bacteria left to handle a 3" fish along with all those other fish, especially all almost at the same time.

After you "cycle" a tank with whatever you used you need to add "one" fish. In time, the bacteria will multiply to handle the waste from that one fish, then add another fish and wait.

You overloaded your very new system and the fish died from ammonia poisoning which also would make them gasp from the surface and maybe die with their mouths wide open.

You did nothing else wrong. Your ammonia reading of .025 is unacceptable which indicates that your level of bacteria isn't sufficient to handle the wastes. The reading was probably higher just before the fish died but the bacteria you now have is processing it, just not fast enough.

A tank continues to "cycle" for the life of the system. The more livestock we add, the more bacteria needs to multiply but it takes time. When we remove fish, there will be less bacteria as they grow according to conditions.
Keep what you have alive and don't add anything for aa few weeks, all will be fine.
Good luck.

 

[Pbh-reef]

Without any visible disease and such sudden deaths my guess is something in the air - is someone using bleach or windex or a spray insect repellent or something similar? Once as a teenager I water proofed my shoes with spray and my fish died from the fumes that day.

 

[Pbh-reef]

I say, Nope, Nope and Nope. This is a very easy diagnosis and I hate to diagnose from afar where I can't see how the fish died.
This is the problem and it is a problem many people don't think of.
When you "cycle" a tank, that just means the tank has enough bacteria in it to oxidize a frozen shrimp. goldfish, T Bone steak or whatever you used to cycle it with. There isn't any more bacteria left to handle a 3" fish along with all those other fish, especially all almost at the same time.

After you "cycle" a tank with whatever you used you need to add "one" fish. In time, the bacteria will multiply to handle the waste from that one fish, then add another fish and wait.

You overloaded your very new system and the fish died from ammonia poisoning which also would make them gasp from the surface and maybe die with their mouths wide open.

You did nothing else wrong. Your ammonia reading of .025 is unacceptable which indicates that your level of bacteria isn't sufficient to handle the wastes. The reading was probably higher just before the fish died but the bacteria you now have is processing it, just not fast enough.

A tank continues to "cycle" for the life of the system. The more livestock we add, the more bacteria needs to multiply but it takes time. When we remove fish, there will be less bacteria as they grow according to conditions.
Keep what you have alive and don't add anything for aa few weeks, all will be fine.
Good luck.

I think ammonia poisoning is also possible but the api test kits are often said to give false positives when ammonia is 0. Get yourself a Red Sea or salifert ammonia kit and a seachem ammonia badge for now.

 

[Sako338]

What is the water temp, I didn’t see a heater in the picture. Maybe it’s hidden. I guess I see the cord to it maybe.

 

[vetteguy53081]

I say, Nope, Nope and Nope. This is a very easy diagnosis and I hate to diagnose from afar where I can't see how the fish died.
This is the problem and it is a problem many people don't think of.
When you "cycle" a tank, that just means the tank has enough bacteria in it to oxidize a frozen shrimp. goldfish, T Bone steak or whatever you used to cycle it with. There isn't any more bacteria left to handle a 3" fish along with all those other fish, especially all almost at the same time.

After you "cycle" a tank with whatever you used you need to add "one" fish. In time, the bacteria will multiply to handle the waste from that one fish, then add another fish and wait.

You overloaded your very new system and the fish died from ammonia poisoning which also would make them gasp from the surface and maybe die with their mouths wide open.

You did nothing else wrong. Your ammonia reading of .025 is unacceptable which indicates that your level of bacteria isn't sufficient to handle the wastes. The reading was probably higher just before the fish died but the bacteria you now have is processing it, just not fast enough.

A tank continues to "cycle" for the life of the system. The more livestock we add, the more bacteria needs to multiply but it takes time. When we remove fish, there will be less bacteria as they grow according to conditions.
Keep what you have alive and don't add anything for aa few weeks, all will be fine.
Good luck.

Pretty much what I indicated. You are on track with observation