So What Happened to My Eel

Thalasstronaut

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Hello,

I lost my snowflake eel yesterday, which is greatly upsetting. He was the reason I made the switch to saltwater tanks last year, I’ve had him since December. I’m just looking for a likely explanation. If I decide to get another eel, I don’t want to go through this again. He was about 9 or 10 inches if I had to guess.

As background, this is a 90 gallon display with a 40 sump. This tank has been running since March, an upgrade over a 40 breeder I was running before that. Just added GSP a month ago, but no other coral.

Ammonia- 0
Nitrite- 0
Nitrate- 5
Ph- 8.0
Salinity- 1.027
Phosphate- .25

I was in the process of lowering salinity from 1.029 over the last week. I don’t know if that was too sudden of a shock.

Other fish are:

2 percula clowns.
Starry blenny.
Flame hawk fish.
Coral beauty in the sump.

CUC:
Tons of snails, nerites, ceriths, trochus, a tiger conch, etc. Nothing really unique.
Two Mithras crabs.
Maybe a dozen or so hermits.
1 pinto crab.

Two nights ago, I noticed my eel looking a bit lethargic, instead of poking his head out of the rockwork, he was drooping and letting his head hang, rather than alertly looking around. It was right before lights out and I assumed he was just being an eel, or maybe eyeing something on the underside of the rock. The next morning (yesterday) he was in the same pose, elsewhere in the tank. Just looking kind of lifeless, maybe breathing a little faster than usual. He was due for a feeding anyway, but showed absolutely no interest in the food. Usually I turn off the power head and he perks right up and goes cruising, but I was holding his food right in front of him and he barely looked at it.

He moved throughout the tank through the day, but would list onto his side and rest in the sand, which is unusual. When he got to a better place of visibility, I could see that the area around his mouth was discolored red, and that his belly looked pinched, and emaciated.

I set up a hospital tank and when I went to move him, he provided no real resistance. He seemed to acknowledge being picked up, but there was no fight or attempt to escape. He only lasted about an hour in the sick tank before I noticed him completely deceased. When I put him in, I had to unplug the power head because the flow was too strong and he couldn’t even swim into his hide.

Things that might be relevant:

Diet: I fed him a couple of times per week. I got a mix of seafood from the grocery store: salmon, raw shrimp, scallops, squid, and octopus. I would chop it up and freeze individual portions of the mix. I used an ice cube tray and he sometimes ate half an ice cube’s worth, sometimes the whole thing. Over the last month, he seemed to go easier on the feedings and not be as hungry, but that also coincides with me adding LRS fish frenzy to the rotation for the rest of the tank, and I definitely saw him occasionally snag bits of that when I dumped it in. So I assumed he wasn’t as hungry at feeding time. He always took something, though.

Recent changes: I just added a batch of snails and crabs from ReefCleaners last week. I do his every couple of months. I had a zebra turbo snail die soon after acclimation.

I also lost a bubble tip anemone around the same time. I had added it about a month ago and it never really seemed to thrive and passed away. I was worried about an ammonia spike but nothing else in the tank was affected and I tested the water and got no ammonia, period.

About three weeks ago, I lost two fish, a yellow angelfish and a Solon fairy wrasse. One day I came down in the morning and the wrasse looked like death, lying on the sand and gasping. I moved him to my hospital tank but he passed. I couldn’t find the yellow angel to save my life. About two days later he was dislodged from wherever he was hiding and floated to the top. He had obviously been fed on. I’m wondering if he was in the eel’s lair (I have a buried length of PVC at the back of the tank) and if he had some kind of parasite and the eel fed on him, could he have contracted it? This is a long shot, I know. The angel was way too big for the eel to eat, and he had never shown any interest in picking at fish. I have no explanation for the double fish death.

Maybe nothing but my eel had a habit of carrying snail shells to the front of the tank. Not always in the same spot, but he would grab one and swim to the front and drop it. Like the whole area near his pipe would be removed of snails and snail shells. I’m struggling to think of a way he could be injured by this, I would maybe worry about choking on a shell but that just doesn’t fit how events turned out.

There is also a good amount of GHA and Dinos in my tank, but again, not sure if this would impact an eel in anyway. If anyone has any ideas, I’d love to figure this out.
 

ISpeakForTheSeas

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Diet: I fed him a couple of times per week. I got a mix of seafood from the grocery store: salmon, raw shrimp, scallops, squid, and octopus.
Between the shrimp and scallops, this diet may be pretty high in thiaminase, so that could definitely cause issues over time, but I doubt that was the cause of death here.

Personally, between the belly looking pinched an emaciated and the other fish deaths, I'd be inclined to think internal parasites may have been at play here, but I'll leave that up to the experts to determine for sure. Did you follow any sort of quarantine protocol for the fish/inverts/etc.?

My post linked below has good feeding info, but the short version:
With regards to the long-term diet, I'd suggest adding a good, fatty fish like salmon (the gold-standard) or mackerel (a good, second place), squid is a good one to add, crabs too if you can do so without breaking the bank, and then I'd also add in some algae (preferably multiple types) to get a few more vitamins and minerals in there that might not be supplied by the meat.

With all the foods, the fresher the better, and the more intact the shrimp is (head, tail, shell, etc.) the better. Ulva, Halymenia, and Nori would be my first suggestions for algae to add, but others like Porphyra and Spirulina would be good too. I doubt the eel would eat the algae by itself, so supplementing it either with algae pellets (such as NLS Marine Fish Pellets), an algal gelatin feed, or through something like wrapping the meat in the algae would be my suggestion.
Predators typically get their "vegetables" (like algae) from their prey - when they eat the herbivores, they eat the vegetables in the prey's organs too.

So, they may or may not purposefully eat the vegetables, but they often still play an important in predator health/nutrition.
 

vetteguy53081

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Hello,

I lost my snowflake eel yesterday, which is greatly upsetting. He was the reason I made the switch to saltwater tanks last year, I’ve had him since December. I’m just looking for a likely explanation. If I decide to get another eel, I don’t want to go through this again. He was about 9 or 10 inches if I had to guess.

As background, this is a 90 gallon display with a 40 sump. This tank has been running since March, an upgrade over a 40 breeder I was running before that. Just added GSP a month ago, but no other coral.

Ammonia- 0
Nitrite- 0
Nitrate- 5
Ph- 8.0
Salinity- 1.027
Phosphate- .25

I was in the process of lowering salinity from 1.029 over the last week. I don’t know if that was too sudden of a shock.

Other fish are:

2 percula clowns.
Starry blenny.
Flame hawk fish.
Coral beauty in the sump.

CUC:
Tons of snails, nerites, ceriths, trochus, a tiger conch, etc. Nothing really unique.
Two Mithras crabs.
Maybe a dozen or so hermits.
1 pinto crab.

Two nights ago, I noticed my eel looking a bit lethargic, instead of poking his head out of the rockwork, he was drooping and letting his head hang, rather than alertly looking around. It was right before lights out and I assumed he was just being an eel, or maybe eyeing something on the underside of the rock. The next morning (yesterday) he was in the same pose, elsewhere in the tank. Just looking kind of lifeless, maybe breathing a little faster than usual. He was due for a feeding anyway, but showed absolutely no interest in the food. Usually I turn off the power head and he perks right up and goes cruising, but I was holding his food right in front of him and he barely looked at it.

He moved throughout the tank through the day, but would list onto his side and rest in the sand, which is unusual. When he got to a better place of visibility, I could see that the area around his mouth was discolored red, and that his belly looked pinched, and emaciated.

I set up a hospital tank and when I went to move him, he provided no real resistance. He seemed to acknowledge being picked up, but there was no fight or attempt to escape. He only lasted about an hour in the sick tank before I noticed him completely deceased. When I put him in, I had to unplug the power head because the flow was too strong and he couldn’t even swim into his hide.

Things that might be relevant:

Diet: I fed him a couple of times per week. I got a mix of seafood from the grocery store: salmon, raw shrimp, scallops, squid, and octopus. I would chop it up and freeze individual portions of the mix. I used an ice cube tray and he sometimes ate half an ice cube’s worth, sometimes the whole thing. Over the last month, he seemed to go easier on the feedings and not be as hungry, but that also coincides with me adding LRS fish frenzy to the rotation for the rest of the tank, and I definitely saw him occasionally snag bits of that when I dumped it in. So I assumed he wasn’t as hungry at feeding time. He always took something, though.

Recent changes: I just added a batch of snails and crabs from ReefCleaners last week. I do his every couple of months. I had a zebra turbo snail die soon after acclimation.

I also lost a bubble tip anemone around the same time. I had added it about a month ago and it never really seemed to thrive and passed away. I was worried about an ammonia spike but nothing else in the tank was affected and I tested the water and got no ammonia, period.

About three weeks ago, I lost two fish, a yellow angelfish and a Solon fairy wrasse. One day I came down in the morning and the wrasse looked like death, lying on the sand and gasping. I moved him to my hospital tank but he passed. I couldn’t find the yellow angel to save my life. About two days later he was dislodged from wherever he was hiding and floated to the top. He had obviously been fed on. I’m wondering if he was in the eel’s lair (I have a buried length of PVC at the back of the tank) and if he had some kind of parasite and the eel fed on him, could he have contracted it? This is a long shot, I know. The angel was way too big for the eel to eat, and he had never shown any interest in picking at fish. I have no explanation for the double fish death.

Maybe nothing but my eel had a habit of carrying snail shells to the front of the tank. Not always in the same spot, but he would grab one and swim to the front and drop it. Like the whole area near his pipe would be removed of snails and snail shells. I’m struggling to think of a way he could be injured by this, I would maybe worry about choking on a shell but that just doesn’t fit how events turned out.

There is also a good amount of GHA and Dinos in my tank, but again, not sure if this would impact an eel in anyway. If anyone has any ideas, I’d love to figure this out.
Without pics will be hard to determine but going forward, I dont believe a dietary issue. They do not need frequent feedings as many assume, due to the many fatty foods they consume which leads to nitrate issues which they do not do well with. Filtration is important and how are you testing the water values?
Additionally, if the salinity rose gradually with the fish in the system, while high should not be a cause but perhaps contributor.
When the eel was discovered, any discoloration, mainly on the belly area? Your phos is elevated and are you adding any tap water ?
Phos best at .06 - .1
 
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Thalasstronaut

Thalasstronaut

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Without pics will be hard to determine but going forward, I dont believe a dietary issue. They do not need frequent feedings as many assume, due to the many fatty foods they consume which leads to nitrate issues which they do not do well with. Filtration is important and how are you testing the water values?
Additionally, if the salinity rose gradually with the fish in the system, while high should not be a cause but perhaps contributor.
When the eel was discovered, any discoloration, mainly on the belly area? Your phos is elevated and are you adding any tap water ?
Phos best at .06 - .1
I am testing water values with an api test kit. There was no discoloration except around the mouth. It was pinkish red.

I’m not sure what you mean when you ask if I am adding tap water though?
 

littlefoxx

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You mentioned his face was red, did it look like an injury?

And he means just tap water from the sink/hose without running it through a RODI system
 

vetteguy53081

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I am testing water values with an api test kit. There was no discoloration except around the mouth. It was pinkish red.

I’m not sure what you mean when you ask if I am adding tap water though?
I would highly suggest taking a water sample to an LFS that does not use API kits and see what readings they come up with and to compare with yours as while some have done ok with this kit, it has also failed many. Salifert as well as Hanna brand are very reliable
Are you using tap water to mix your salt or for topping off tank when water evaporates?
 
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Thalasstronaut

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I would highly suggest taking a water sample to an LFS that does not use API kits and see what readings they come up with and to compare with yours as while some have done ok with this kit, it has also failed many. Salifert as well as Hanna brand are very reliable
Are you using tap water to mix your salt or for topping off tank when water evaporates?
Oh, yes, I use tap water.
 

vetteguy53081

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Oh, yes, I use tap water.
Tap can have adverse effect, being low in PH, adds minerals and the list goes on. If No RODI water, use drinking or distilled water
 

littlefoxx

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Oh, yes, I use tap water.
So no RODI? Thats most likely why your eel passed and the other fish. Theres elements in tap water that are bad for fish
 

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