Mysterious angelfish death

[enricosonic]

A couple of days ago one of my angelfish began darting rather aggressively at no other fish, almost as if it received an electric shock. It appeared involuntary like a seizure for lack of a better term. His voracious appetite also stopped. This morning he was dead. I tested for ammonia and nitrites, but as the tank is 75 gallons and these are small (1” diameter bodies) fish, I don’t think it posed any real threat to the water chemistry and the tests bore that out. Nevertheless I did a 50% water change moments ago.

For some more info, this was one of four angelfish. Completed a fishless cycle about 3-4 weeks ago, days later the fish were added. Parameters have been spot on, temp 80°, very soft water here. All other fish (six corys, one clown pleco) are frolicking and appear quite healthy. But so did the angelfish that died suddenly last night before approximately 48 hours ago when I noticed him moving in this jerking fashion. Again, it appeared involuntary. Prior to adding him to my tank, he’d been in my daughter’s tank for nearly 3 months. Healthy and active up to two days ago.

The other two angels were added 10 days ago, from a reputable LFS but I did not quarantine them and I suppose I should always do this moving forward. But worth noting, they are currently active and seemingly in good health.

Could this have been a parasite? He had no discoloration or spots, nor any growths. I’m concerned for the health of the others now.

 

[enricosonic]

BTW, the angelfishes’ diet is Bug Bites flakes and/or pellets. Plus they steal some of the bottom feeder wafers.

 

[Oblio]

Parameters have been spot on

What were the parameters?

 

[enricosonic]

What were the parameters?

Ammonia 0, nitrite 0, nitrate about 20 ppm, a little below really, pH is 6.8. GH roughly 50-60 ppm. KH is more or less same number. This is the API kit, took 3 drops to yellow, 4 drops to turn bright yellow.

 

[enricosonic]

Part of the odd physical behavior was occasional rapid twitching of the ventral fins.

 

[Oblio]

I'm far from knowledgeable in fish diagnosis but if your parameters are good (I'd try to get the Nitrates lower), and the other fish have no symptoms or physical indications, I would keep monitoring water params and fish.

Note: I asked for water parameter metrics because those who know more than I will surely ask, and that way the numbers will be here when they read the thread.

 

[enricosonic]

I'm far from knowledgeable in fish diagnosis but if your parameters are good (I'd try to get the Nitrates lower), and the other fish have no symptoms or physical indications, I would keep monitoring water params and fish.

Note: I asked for water parameter metrics because those who know more than I will surely ask, and that way the numbers will be here when they read the thread.

Yeah, gotcha - frankly I’ve been on the forum long enough to know I should’ve provided numbers from the start.

 

[enricosonic]

Nitrates are actually fine, close to zero but certainly between 0-.5 ppm. This was taken after the water change.

 

[azvictoria]

A couple of days ago one of my angelfish began darting rather aggressively at no other fish, almost as if it received an electric shock. It appeared involuntary like a seizure for lack of a better term. His voracious appetite also stopped. This morning he was dead. I tested for ammonia and nitrites, but as the tank is 75 gallons and these are small (1” diameter bodies) fish, I don’t think it posed any real threat to the water chemistry and the tests bore that out. Nevertheless I did a 50% water change moments ago.

For some more info, this was one of four angelfish. Completed a fishless cycle about 3-4 weeks ago, days later the fish were added. Parameters have been spot on, temp 80°, very soft water here. All other fish (six corys, one clown pleco) are frolicking and appear quite healthy. But so did the angelfish that died suddenly last night before approximately 48 hours ago when I noticed him moving in this jerking fashion. Again, it appeared involuntary. Prior to adding him to my tank, he’d been in my daughter’s tank for nearly 3 months. Healthy and active up to two days ago.

The other two angels were added 10 days ago, from a reputable LFS but I did not quarantine them and I suppose I should always do this moving forward. But worth noting, they are currently active and seemingly in good health.

Could this have been a parasite? He had no discoloration or spots, nor any growths. I’m concerned for the health of the others now.

I have had a few angels over many years concuss themselves and expire. I've had them for 30 years or so, it's not that common but certainly possible. If they were fairly new, it could have really crashed into something by being startled. Some creatures are also 'failure to thrive'. There may be no explanation other than a misfire in the body/genes or a major startle.. Do quarantine moving forward, and angels like a lot of cover/plants. A lot of live plants can help brace a fish from hitting things too hard.

 

[enricosonic]

I have had a few angels over many years concuss themselves and expire. I've had them for 30 years or so, it's not that common but certainly possible. If they were fairly new, it could have really crashed into something by being startled. Some creatures are also 'failure to thrive'. There may be no explanation other than a misfire in the body/genes or a major startle.. Do quarantine moving forward, and angels like a lot of cover/plants. A lot of live plants can help brace a fish from hitting things too hard.

I appreciate your input and frankly I hadn't considered a crash. It's indeed possible even if it seems unlikely. I say that because while there's a lot of room, that "room" is filled and/or partially blocked with plants/driftwood/rock.

This the one who rather abruptly died. Very sad.