Looking for help with sudden unexplained deaths of fish

boomshockpow

New Member
View Badges
Joined
Nov 22, 2024
Messages
14
Reaction score
5
Location
Audubon
What state or country do you live in
Pennsylvania
Rating - 0%
0   0   0
Good afternoon!

My saltwater tank has been up since.. November(?) of last year. I waited a long time to ensure it cycled, used live sand, dry rock, lots of filter media, etc. This isn't my first tank so I have experience, though I am not an expert by any means. I've had a moon jelly tank, and a few freshwater tanks, one that's been up for about two years. I added fish in late January to my current saltwater tank, and everybody was fine. I started with two clowns, as is the rules. I also grabbed a Tequila Turbo snail. Then in mid February I went to a new fish store (which maybe was my problem) and got a Banggai cardinalfish and a fire goby, as well as a couple more snaills. Two nassarius and one fighting conch.

Everybody ate well. I fed a wide variety of food twice a day. Enough so that they ate and seemed full, but not so much that it was a cloud of food. I was doing weekly water changes, and keeping an eye on nitrates specifically, but also occasionally checking other things. I keep a lid on the tank and normally wash my hands, and often times wear gloves when dealing with this tank, because I'm ascared of unfamiliar toxins and things. Nitrates were usually in the 5-10 neighborhood at the most. About 2.5-3 weeks after introducing the cardinalfish, goby and newer snails.. Disaster struck.

I fed everyone at around 6 PM as is normal. I do 9 AM and 6 PM. Everyone seemed happy to eat and I saw no odd swimming behavior, discolorations, white spots, etc. Everyone seemed OK. They ate their few bites, and then went about their evening. The next morning I happened to be up early at around 6 AM, and one clownfish was lying upside down in the sand motionless, and the other one was clearly in distress. It was lying in the sand and when I brushed gently up against it, it jerked and started swimming erratically, clearly struggling to swim. It died about an hour later. The erratic swimming I saw reminded me of swim bladder disease, which I have seen before. Unlike swim bladder disease, it came on and killed in less than twelve hours, and I had been pretty careful to not only vary the diet with all kinds of things, but also to not overfeed.

I do keep an emergency bag of charcoal nearby (not that I could think of any toxins that had been introduced), so I tossed that in the tank and kept an eye on the other two fish I have. I also reduced feedings to once per day. Everyone had been enjoying the once daily feedings and getting along nicely. The cardinalfish mostly just hovered around as they do (or maybe darted in place is the way to say it) and the fire goby did much of the same, though he occasionally liked to hide in the holes/crevices of the rock formations.

I did a water change the next day, because I had to heat up and mix some water and reef salt. So now we're about a week later, last Wednesday or Thursday. I noticed that the cardinalfish was just gone without a trace. I looked all over and found no remains, either outside the tank (though I do have a lid that mostly covers the tank) nor on the sandbed. I looked for hours to no avail. Goby the fire goby was doing OK, still seemed pretty normal. I assumed something must be wrong, so I checked all the parameters and they were totally fine. Ammonia 0, Nitrite 0, Nitrate was 5ish, Phosphate < .25, Calcium around 400, PH around 8, salinity a right around 1.0245.

Goby got really shy and started hiding much more. About two days later he never stopped hiding and disappeared entirely. I did a water change today with similar parameters to above, although nitrates were less than 5, likely because there isn't as much waste being created anymore. I was doing them weekly to keep a handle on the relatively new bioload changes, but I guess now I can probably go to biweekly or whatever is needed.

Does anyone have any ideas of what could have happened here? I have been grasping at straws that maybe it was that I went to a new store, maybe it was a parasite, or some bacterial disease. But I don't know what I could have done better to have prevented it. It's had me feeling sad that I lost my new friends, but also discouraged. I would love any advice, if someone has the time.


Thanks in advance.
 
Could be many things based on what you are saying

Introduction of Disease or Parasites from the New Fish Store
Toxin Introduction
Water Quality or Parameter Fluctuations
Stress from Overcrowding or Aggression
Hidden Predator or Hitchhiker
Bacterial Infection such as vibriosis

The disappearance of the cardinalfish and fire goby without trace could indicate a hidden predator or hitchhiker (e.g., a bristleworm, mantis shrimp, or other organism) that was introduced with the live rock or sand. However, this wouldn’t explain the sudden death of the clownfish.
Bacterial Infection


My guess ? A power outage during the night cut off the oxygen supply.
 
What is the tank size?
Do you have algae? Massive algae problem can deplete oxygen at night
How is the water oxygenated?

Pictures can help to generate more idea's
 
My fire fish died overnight and in the matter of hours, only the head remained. Inverts are crazy fast by the way.
 
What is the tank size?
Do you have algae? Massive algae problem can deplete oxygen at night
How is the water oxygenated?

Pictures can help to generate more idea's
Thanks for your reply! I do have algae, but not a ton. Just some on the glass and a reasonable amount of hair algae.

I ordered some macro algae to actually help with the phosphate a bit, may help with the oxygenation too. I don't have an air stone or anything like that
 
My fire fish died overnight and in the matter of hours, only the head remained. Inverts are crazy fast by the way.
Yeah I sort of figured the inverts were on it. They were on my clown before it's body was even cold. Wild stuff.
 
Could be many things based on what you are saying

Introduction of Disease or Parasites from the New Fish Store
Toxin Introduction
Water Quality or Parameter Fluctuations
Stress from Overcrowding or Aggression
Hidden Predator or Hitchhiker
Bacterial Infection such as vibriosis

The disappearance of the cardinalfish and fire goby without trace could indicate a hidden predator or hitchhiker (e.g., a bristleworm, mantis shrimp, or other organism) that was introduced with the live rock or sand. However, this wouldn’t explain the sudden death of the clownfish.
Bacterial Infection


My guess ? A power outage during the night cut off the oxygen supply.
Yeah I'd lean away from the sand being the issue, just caribsea live sand and the rock was dry rock, I think that's the right term. Like concrete with holes in it. Not live rock.

I would be curious about if maybe there was some other way a hitchhiker could have gotten in though.

It's funny, someone else mentioned oxygen too, and I can wholeheartedly guarantee it wasn't a power outage. My tanks have massive enterprise grade UPS setups, so at least I can check that one off. But macro algae would probably not hurt for sure
 
Yeah I'd lean away from the sand being the issue, just caribsea live sand and the rock was dry rock, I think that's the right term. Like concrete with holes in it. Not live rock.

I would be curious about if maybe there was some other way a hitchhiker could have gotten in though.

It's funny, someone else mentioned oxygen too, and I can wholeheartedly guarantee it wasn't a power outage. My tanks have massive enterprise grade UPS setups, so at least I can check that one off. But macro algae would probably not hurt for sure
Have you ever simulated a power outage for 5 min to make sure everything works the way you intended it to work ?
 
Have you ever simulated a power outage for 5 min to make sure everything works the way you intended it to work ?
I sure have. This setup is good with the heater on for about 8 hours. And it alarms annoyingly. Hard to miss.

But I think power is the least of my worries, because your suggestions are mostly valid. What can I do to reduce the potential for sneaky hitchhikers?
 
Good afternoon!

My saltwater tank has been up since.. November(?) of last year. I waited a long time to ensure it cycled, used live sand, dry rock, lots of filter media, etc. This isn't my first tank so I have experience, though I am not an expert by any means. I've had a moon jelly tank, and a few freshwater tanks, one that's been up for about two years. I added fish in late January to my current saltwater tank, and everybody was fine. I started with two clowns, as is the rules. I also grabbed a Tequila Turbo snail. Then in mid February I went to a new fish store (which maybe was my problem) and got a Banggai cardinalfish and a fire goby, as well as a couple more snaills. Two nassarius and one fighting conch.

Everybody ate well. I fed a wide variety of food twice a day. Enough so that they ate and seemed full, but not so much that it was a cloud of food. I was doing weekly water changes, and keeping an eye on nitrates specifically, but also occasionally checking other things. I keep a lid on the tank and normally wash my hands, and often times wear gloves when dealing with this tank, because I'm ascared of unfamiliar toxins and things. Nitrates were usually in the 5-10 neighborhood at the most. About 2.5-3 weeks after introducing the cardinalfish, goby and newer snails.. Disaster struck.

I fed everyone at around 6 PM as is normal. I do 9 AM and 6 PM. Everyone seemed happy to eat and I saw no odd swimming behavior, discolorations, white spots, etc. Everyone seemed OK. They ate their few bites, and then went about their evening. The next morning I happened to be up early at around 6 AM, and one clownfish was lying upside down in the sand motionless, and the other one was clearly in distress. It was lying in the sand and when I brushed gently up against it, it jerked and started swimming erratically, clearly struggling to swim. It died about an hour later. The erratic swimming I saw reminded me of swim bladder disease, which I have seen before. Unlike swim bladder disease, it came on and killed in less than twelve hours, and I had been pretty careful to not only vary the diet with all kinds of things, but also to not overfeed.

I do keep an emergency bag of charcoal nearby (not that I could think of any toxins that had been introduced), so I tossed that in the tank and kept an eye on the other two fish I have. I also reduced feedings to once per day. Everyone had been enjoying the once daily feedings and getting along nicely. The cardinalfish mostly just hovered around as they do (or maybe darted in place is the way to say it) and the fire goby did much of the same, though he occasionally liked to hide in the holes/crevices of the rock formations.

I did a water change the next day, because I had to heat up and mix some water and reef salt. So now we're about a week later, last Wednesday or Thursday. I noticed that the cardinalfish was just gone without a trace. I looked all over and found no remains, either outside the tank (though I do have a lid that mostly covers the tank) nor on the sandbed. I looked for hours to no avail. Goby the fire goby was doing OK, still seemed pretty normal. I assumed something must be wrong, so I checked all the parameters and they were totally fine. Ammonia 0, Nitrite 0, Nitrate was 5ish, Phosphate < .25, Calcium around 400, PH around 8, salinity a right around 1.0245.

Goby got really shy and started hiding much more. About two days later he never stopped hiding and disappeared entirely. I did a water change today with similar parameters to above, although nitrates were less than 5, likely because there isn't as much waste being created anymore. I was doing them weekly to keep a handle on the relatively new bioload changes, but I guess now I can probably go to biweekly or whatever is needed.

Does anyone have any ideas of what could have happened here? I have been grasping at straws that maybe it was that I went to a new store, maybe it was a parasite, or some bacterial disease. But I don't know what I could have done better to have prevented it. It's had me feeling sad that I lost my new friends, but also discouraged. I would love any advice, if someone has the time.


Thanks in advance.
How are you testing water and what is your method of filtration?
Are you using RODI water only or also tap water from faucet?
 
I sure have. This setup is good with the heater on for about 8 hours. And it alarms annoyingly. Hard to miss.

But I think power is the least of my worries, because your suggestions are mostly valid. What can I do to reduce the potential for sneaky hitchhikers?
Good.

Inspect the fish, invert, coral closely when you are buying,dipping, acclimating it to the tank. Look at night with a red light in the tank to see if you catch a glimpse of something. The tank sounds new, so I doubt something small grew to something bigger quickly to eat the fish.

Do you have a skimmer ? They help with oxygen, also aiming the pump higher towards the surface helps break the water tension and oxygenate it.
 
How are you testing water and what is your method of filtration?
Are you using RODI water only or also tap water from faucet?
I have a few big API kits I use for testing. I use a RODI filter for water
 

Attachments

  • PXL_20250315_005039831.jpg
    PXL_20250315_005039831.jpg
    139.9 KB · Views: 41
  • PXL_20250315_005044693.MP.jpg
    PXL_20250315_005044693.MP.jpg
    185.7 KB · Views: 38
Good.

Inspect the fish, invert, coral closely when you are buying,dipping, acclimating it to the tank. Look at night with a red light in the tank to see if you catch a glimpse of something. The tank sounds new, so I doubt something small grew to something bigger quickly to eat the fish.

Do you have a skimmer ? They help with oxygen, also aiming the pump higher towards the surface helps break the water tension and oxygenate it.
My HOB filter has a skimmer? I think anyway. It's a tidal 55 filter.
 
Here are some photos. It's a tidal 55 HOB filter in the back
This is an Ok filter and likely not keeping up with flow needs and water movement and the UV is likely not strong enough as there is a lot of mulm and sediment in the pics. API kits are tricky and you may be getting false results. I encourage you verify your water and readings by taking a water sample to a shop that does not test with Ai and see what results they come up with
 
This is an Ok filter and likely not keeping up with flow needs and water movement and the UV is likely not strong enough as there is a lot of mulm and sediment in the pics. API kits are tricky and you may be getting false results. I encourage you verify your water and readings by taking a water sample to a shop that does not test with Ai and see what results they come up with
I have this combined with a low tier wave maker. How could I make it better? What filter would you recommend?

I can go to a shop. The closest one is about 45 minutes away that doesn't use API. But the tests have generally been adequate with my other tanks that have been up longer. I even have two different nitrate API tests I run. I feel like beyond that the only local solution is to get one of those digital testers which I think are pretty expensive.
 
I have this combined with a low tier wave maker. How could I make it better? What filter would you recommend?

I can go to a shop. The closest one is about 45 minutes away that doesn't use API. But the tests have generally been adequate with my other tanks that have been up longer. I even have two different nitrate API tests I run. I feel like beyond that the only local solution is to get one of those digital testers which I think are pretty expensive.
Hang-on refugium along with hang-on skimmer such as Ice Cap K1-100
 

TOP 10 Trending Threads

WHICH KIND OF INVERT HAS CAUSED THE MOST MISCHIEF IN YOUR TANK?

  • Sea urchins

    Votes: 6 24.0%
  • Hermit crabs

    Votes: 3 12.0%
  • Other crabs

    Votes: 3 12.0%
  • Shrimp

    Votes: 1 4.0%
  • Snails or conchs

    Votes: 1 4.0%
  • Sea stars

    Votes: 0 0.0%
  • Anemones

    Votes: 5 20.0%
  • None! My inverts are model citizens. :-)

    Votes: 4 16.0%
  • Something else (tell us in the comments)

    Votes: 2 8.0%
Back
Top
Home
Post thread…
Market
What's new