Angels dying one by one

[Librarymouse]

In the past month I've lost 4 angelfish to seemingly the same symptoms, one by one. They become unable to swim well and stay at the bottom of the tank on their side. Today a 5th has exhibited the same symptoms. Also all my angels seem stressed and are opening & closing their mouths probably due to temperature? I have a bubbler, it's a 75 gallon planted tank, fx6 filter, with currently 6 angels, guppies, kuhli loaches, & hillstream loaches. My PH is 7.3 as of yesterday, my ammonia is 0ppm, my nitrates have recently gone up to 10, & my nitrites are at 0. Recently my heater died & the tank got really cold, still working on upping that (currently at 74f) but they've been dying since before then. I've also recently changed out filter media, but they've been dying since before that, too. I've tried adding a small bit (1tbsp) of aquarium salt to help last week, & have also tried a 4 day fast with peas on the 4th day a few days ago. I just want to know the cause and how to fix it. Appreciate any advice

 

[Magnum Man]

we'll need more info... ( like water hardness )... I can't tell you how many angels I tried to get going here ( super hard water is not an angels friend, & I ended up adding a dedicated RO Filter for aquarium water... you don't mention your species of Hillstreams ( there are 100's ), and most like cooler water ( unfortunately angels do not like cooler water )... Guppies typically like hard water, and most of the other fish listed like softer water...

I can say do as I say, not as I do... but a lot of aquarists like using 2 heaters... mostly they want more even temperature, I don't believe the fish need exactly the same temp from side to side, but the advantage of two, gives you some time to replace a bad one, while the other is chugging along... in my defense, of using just one heater, I keep several spare heaters on hand, & always have a NIB heater, because of how many tanks I have...

angels are a finicky fish, are you noticing any bullying??? I had to break up a sibling pair, as the bigger one, must have started displaying dominance, and the other went to a bottom corner, & quit eating, it required me to move it...

 

[Uberhoust]

Agree with @Magnum Man any more details you can share would be helpful. I keep Angels in a 75 gallon tank and by accident ended up letting the temp drop to 60 degrees once (main reason I now have a temperature regulator for filling the tank). I had one Angel sink to the bottom and lay on its side but once the water temp got back to the normal 75 she was OK. This was over a year ago. I think you might need to consider less common issues.

 

[fishorama]

How long has you tank been set up? Any new fish? as of when? It could be they brought in a disease, or not. Could be the heater failure, I wonder how long the temp had been dropping. I believe heaters are still the weakest part of our hobby equipment (at least they don't seem to stick on & cook the fish as the old time HOB heaters did.). I only have 1 heated tank now but have 2 heaters in it. As Magnum said, angels can't handle too cold, pangios (kuhlis) like it warmer too. How do they seem? Active & eating? The guppies & hillstreams can handle cooler temps better but how cold did the tank get when you noticed?

Also get or put a thermometer where you can easily see it when feeding. It doesn't have to be in the front if you can see a tank side. I find digitals to be easier to see.

I would slowly remove the salt with a few water changes. It can help with any nitrIte & a few diseases but can stress some fish too. I think of salt as a drug used only if I think it will help with a specific problem not a general tonic. A TBSP in 75g shouldn't harm them but it's not enough to treat anything much either.

Good luck. Please answer our several questions & let us know how your fish are doing.

 

[Librarymouse]

we'll need more info... ( like water hardness )... I can't tell you how many angels I tried to get going here ( super hard water is not an angels friend, & I ended up adding a dedicated RO Filter for aquarium water... you don't mention your species of Hillstreams ( there are 100's ), and most like cooler water ( unfortunately angels do not like cooler water )... Guppies typically like hard water, and most of the other fish listed like softer water...

I can say do as I say, not as I do... but a lot of aquarists like using 2 heaters... mostly they want more even temperature, I don't believe the fish need exactly the same temp from side to side, but the advantage of two, gives you some time to replace a bad one, while the other is chugging along... in my defense, of using just one heater, I keep several spare heaters on hand, & always have a NIB heater, because of how many tanks I have...

angels are a finicky fish, are you noticing any bullying??? I had to break up a sibling pair, as the bigger one, must have started displaying dominance, and the other went to a bottom corner, & quit eating, it required me to move it...

The total hardness is 75, CL2 is 0, total alkalinity is 120, & carbonate is 120. But that's using test strips, as the master testing kit i have only tests for nitrite nitrate ammonia & ph. i haven't noticed any bullying, nor do any look picked on, they all seem to have an appetite, & unfortunately i do not know the specific species of my hillstreams.

 

[Librarymouse]

How long has you tank been set up? Any new fish? as of when? It could be they brought in a disease, or not. Could be the heater failure, I wonder how long the temp had been dropping. I believe heaters are still the weakest part of our hobby equipment (at least they don't seem to stick on & cook the fish as the old time HOB heaters did.). I only have 1 heated tank now but have 2 heaters in it. As Magnum said, angels can't handle too cold, pangios (kuhlis) like it warmer too. How do they seem? Active & eating? The guppies & hillstreams can handle cooler temps better but how cold did the tank get when you noticed?

Also get or put a thermometer where you can easily see it when feeding. It doesn't have to be in the front if you can see a tank side. I find digitals to be easier to see.

I would slowly remove the salt with a few water changes. It can help with any nitrIte & a few diseases but can stress some fish too. I think of salt as a drug used only if I think it will help with a specific problem not a general tonic. A TBSP in 75g shouldn't harm them but it's not enough to treat anything much either.

Good luck. Please answer our several questions & let us know how your fish are doing.

My tank has been set up for abt a year, when this started there were not any new fish, the temp had been dropping overnight and we got a new heater in around maybe 1pm, it had dropped to about 60, my angels are slowly moving throughout the tank and seem mostly normal except for a little stressed mainly shown through mouth movements, the kuhlis & hillstreams seem fine, though i have one cinnamon kuhli that likes to circle a specific wall of the tank, & the guppies (actually endlers, i mixed up the names) are active. My current new heater seems to be having fluctuation problems though. I just got home and it's gone up 3 degrees in aproximately 7 hrs? though it shouldn't of. It's turned up to 75f and it's at 78 now. Could that be the main cause?

 

[fishorama]

Yeah, I'm thinking the angels got too cold. 60F is too low for them. I would not go much above 77-79F. Keep a close eye on temp; it takes heaters fine adjustments to keep it steady. You don't want to go too high or the hillstream loaches will be unhappy. I'm not sure about endlers, I haven't kept them.