Mystery of the Dying Tetras

Gemtrox42

Fish Fanatic
Joined
Dec 9, 2020
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Location
United States
Ammonia 0
Nitrite 0
Nitrate <10
pH 7.3
gH 200 ppm
Chlorine 0

Tanks - 10gal, heavily planted with hornwort, java moss, and amazon swords, gravel bottom with cherry shrimp, a clown pleco and two honey gourami. I use a strip of LEDs for illumination.

I have purchased 3 rounds of cardinal tetras from my LFS over the past few months. They are always active and colorful when I see them in their tanks, and I've checked with the LFS and several employees and they deny having any problems during or after acclimating them. I get eight every time, and every time I've lost 7 or all of them in the first few days in my tank. Twice one died before even getting back to my house - I found them floating upside down in the bag, and during the two hour acclimation they never stirred again. I have a 30g with the same water chemistry and 14 cardinal tetras, and no problems or deaths. I get a money back guarantee so I haven't lost anything but time, but I cannot bring myself to put more fish in danger. My hunch is that there is something my LFS is not letting on, but I won't get any anywhere else either because If I'm wrong I'll kill them. Any advice or suggestions or thoughts are welcome.
 
Ammonia 0
Nitrite 0
Nitrate <10
pH 7.3
gH 200 ppm
Chlorine 0

Tanks - 10gal, heavily planted with hornwort, java moss, and amazon swords, gravel bottom with cherry shrimp, a clown pleco and two honey gourami. I use a strip of LEDs for illumination.

I have purchased 3 rounds of cardinal tetras from my LFS over the past few months. They are always active and colorful when I see them in their tanks, and I've checked with the LFS and several employees and they deny having any problems during or after acclimating them. I get eight every time, and every time I've lost 7 or all of them in the first few days in my tank. Twice one died before even getting back to my house - I found them floating upside down in the bag, and during the two hour acclimation they never stirred again. I have a 30g with the same water chemistry and 14 cardinal tetras, and no problems or deaths. I get a I fee money back guarantee so I haven't lost anything but time, but I cannot bring myself to put more fish in danger. My hunch is that there is something my LFS is not letting on, but I won't get any anywhere else either because If I'm wrong I'll kill them. Any advice or suggestions or thoughts are welcome.

Ammonia 0
Nitrite 0
Nitrate <10
pH 7.3
gH 200 ppm
Chlorine 0

Tanks - 10gal, heavily planted with hornwort, java moss, and amazon swords, gravel bottom with cherry shrimp, a clown pleco and two honey gourami. I use a strip of LEDs for illumination.

I have purchased 3 rounds of cardinal tetras from my LFS over the past few months. They are always active and colorful when I see them in their tanks, and I've checked with the LFS and several employees and they deny having any problems during or after acclimating them. I get eight every time, and every time I've lost 7 or all of them in the first few days in my tank. Twice one died before even getting back to my house - I found them floating upside down in the bag, and during the two hour acclimation they never stirred again. I have a 30g with the same water chemistry and 14 cardinal tetras, and no problems or deaths. I get a money back guarantee so I haven't lost anything but time, but I cannot bring myself to put more fish in danger. My hunch is that there is something my LFS is not letting on, but I won't get any anywhere else either because If I'm wrong I'll kill them. Any advice or suggestions or thoughts are welcome.
I feel for you - I have lost 9 penguin tetras today - no obvious cause - hope you get to the bottom of your issue.

ATB
 
Obviously poor stock from the LFS, avoid them in the future.

BTW, the pleco needs a much bigger tank than 10G, they grow to nearly 4" in length, and have a sizeable bioload.
 
I get eight every time, and every time I've lost 7 or all of them in the first few days in my tank. Twice one died before even getting back to my house - I found them floating upside down in the bag, and during the two hour acclimation they never stirred again.
The fish are either being stressed when caught at the shop, or the fish have only come into the shop recently (in the last few days), or the shop has done a big water change on the day you got them.

Find out what the pH and GH of the shop water is and match your tank water to that. You can adjust it a few weeks later if you need to change it.

Find out when the shop gets fish in and either buy fish the day before new ones come in, or wait until the new fish have been in the shop for a week or more before buying them.

Find out when the shop does water changes and buy the fish the day before they do a water change, or at least 3 days after they do a water change.

Watch the staff member who catches the fish. If they spend more than 20-30 seconds chasing the fish around, tell them to stop and you will come back another time. I have lost plenty of fish because staff chase them around the tank and stress the fish, and the fish die on the way home while still in the bag. It should only take a few seconds to catch a group of tetras out of a shop tank. They should use 1 big net and a smaller one. Put the big net against the side of the tank and guide the fish into it with the smaller net.

If the fish have just come in they will be stressed from the journey and possible change in water chemistry. If those fish are then subject to a water change, it stresses them even more. Then if you buy the fish and take them home and put them in different water again, you can lose the fish.

The fact some fish have died on the way home would suggest stress from being caught and possibly newly imported fish.
 
The fish are either being stressed when caught at the shop, or the fish have only come into the shop recently (in the last few days), or the shop has done a big water change on the day you got them.

Find out what the pH and GH of the shop water is and match your tank water to that. You can adjust it a few weeks later if you need to change it.

Find out when the shop gets fish in and either buy fish the day before new ones come in, or wait until the new fish have been in the shop for a week or more before buying them.

Find out when the shop does water changes and buy the fish the day before they do a water change, or at least 3 days after they do a water change.

Watch the staff member who catches the fish. If they spend more than 20-30 seconds chasing the fish around, tell them to stop and you will come back another time. I have lost plenty of fish because staff chase them around the tank and stress the fish, and the fish die on the way home while still in the bag. It should only take a few seconds to catch a group of tetras out of a shop tank. They should use 1 big net and a smaller one. Put the big net against the side of the tank and guide the fish into it with the smaller net.

If the fish have just come in they will be stressed from the journey and possible change in water chemistry. If those fish are then subject to a water change, it stresses them even more. Then if you buy the fish and take them home and put them in different water again, you can lose the fish.

The fact some fish have died on the way home would suggest stress from being caught and possibly newly imported fish.
This is all fantastic stuff that I didn't consider, thanks! The only problem is my LFS goes through all their cardinal stock in under a week (now that I think about it, whoever is vacuuming up the cardinals is probably experiencing the same problems as me), and they don't take reservations on livestock. Maybe if I explain this to a manager or the owner they can make an exception, but otherwise I'll have to look elsewhere for the future. It's a shame they even let people buy the fish in under a week after acclimation if this is so deadly. But I'm relieved to know that it's not my setup that's killing my fish.
 
Obviously poor stock from the LFS, avoid them in the future.

BTW, the pleco needs a much bigger tank than 10G, they grow to nearly 4" in length, and have a sizeable bioload.
No problem, he's just in quarantine right now. He'll be moving to my 30g in less than a week. I didn't realize their bioload was so large, I might be underfeeding mine then, I've only been feeding it a hikari bottom feeder piece a night.
 
Sorry for your losses.
Do you always acclimate for 2 hours?
I just float the bag for 15 minutes to match the temperature then put them in the quarantine tank.
 
I didn't realize their bioload was so large, I might be underfeeding mine then, I've only been feeding it a hikari bottom feeder piece a night.
Suckermouth catfish and other types of algae eating fish eat a lot and produce a lot of waste. Bristlenose catfish are pretty bad when it comes to the amount of waste a fish produces and a couple of 4 inch fish can dirty up the gravel in a few days.

We used to demonstrate gravel cleaners at the shop and we normally used it on the bristlenose tank because it was always filthy. They are quite messy fish that poop heaps.
 
Suckermouth catfish and other types of algae eating fish eat a lot and produce a lot of waste. Bristlenose catfish are pretty bad when it comes to the amount of waste a fish produces and a couple of 4 inch fish can dirty up the gravel in a few days.

We used to demonstrate gravel cleaners at the shop and we normally used it on the bristlenose tank because it was always filthy. They are quite messy fish that poop heaps.
Is the clown pleco both a bristle and a sucker? And I thought it was a bottom feeder, not an algae eater...uh whoops. Does all this additional waste necessitate using a gravel vac? I don't clean my gravel at the moment.
 
Sorry for your losses.
Do you always acclimate for 2 hours?
I just float the bag for 15 minutes to match the temperature then put them in the quarantine tank.
My understanding is that acclimating longer is safer, but not always necessary. Is that not the case?
 
It's possible its an ammonia spike, what's the lowest reading on your test kit? And which ammonia test do you use? When was your 0 reading taken?
 
Clown plecos are a suckermouth catfish but are not the same fish as a common bristlenose catfish, nor are they the common pleco which grows to 18-24 inches in length. The clown pleco is a small algae eating fish that will pick up uneaten food from the bottom of the tank.

They don't produce as much waste as common bristlenose catfish or common plecos.

All suckermouth catfish should have some driftwood in their tank so they can graze on it. The wood helps their digestion. They should also have access to algae. You can encourage algae to grow on the glass by increasing the lighting period by an hour or two each day. Or you can put smooth rocks or plastic ornaments in a container of water and keep it out in the sun. When the rocks/ ornaments get covered in algae, you put them in the tank for the fish to feed on. When they are free of algae, you rinse them under tap water and put them in the bucket of water outside to grow more algae.

Gravel cleaning should be done on all tanks whenever you do a water change. However, it doesn't have to be done straight away. If you have gravel (not sand) then get a basic model gravel cleaner like the one in the following link and use it when you do a water change.
 
My understanding is that acclimating longer is safer, but not always necessary. Is that not the case?
I think it depends on the circumstances, sometimes it is dangerous.
If the fish have been in the bag a while ammonia will have built up and oxygen will be depleting so it's good to get them out of that water sooner rather than later. Also ammonia is less toxic in acidic water but more so in basic water - so people who add basic water to the bag could be making the conditions worse.
To play it safe I transfer the fish as soon as the temperature has had a chance to equalise. Fish can't acclimate to the other parameters (pH, GH, KH) for weeks, sometimes never if they are very different to those in which the fish evolve, so I see no benefit to it.
 
Clown plecos are a suckermouth catfish but are not the same fish as a common bristlenose catfish, nor are they the common pleco which grows to 18-24 inches in length. The clown pleco is a small algae eating fish that will pick up uneaten food from the bottom of the tank.

They don't produce as much waste as common bristlenose catfish or common plecos.

All suckermouth catfish should have some driftwood in their tank so they can graze on it. The wood helps their digestion. They should also have access to algae. You can encourage algae to grow on the glass by increasing the lighting period by an hour or two each day. Or you can put smooth rocks or plastic ornaments in a container of water and keep it out in the sun. When the rocks/ ornaments get covered in algae, you put them in the tank for the fish to feed on. When they are free of algae, you rinse them under tap water and put them in the bucket of water outside to grow more algae.

Gravel cleaning should be done on all tanks whenever you do a water change. However, it doesn't have to be done straight away. If you have gravel (not sand) then get a basic model gravel cleaner like the one in the following link and use it when you do a water change.
I haven't vaccumed the gravel in over 6 months...should I be experiencing any problems I don't know about? The reason I dont vac is because I have a lot of small delicate plants and I was told that the fish poop can act as a supplemental fertilizer for plants.
 
I think it depends on the circumstances, sometimes it is dangerous.
If the fish have been in the bag a while ammonia will have built up and oxygen will be depleting so it's good to get them out of that water sooner rather than later. Also ammonia is less toxic in acidic water but more so in basic water - so people who add basic water to the bag could be making the conditions worse.
To play it safe I transfer the fish as soon as the temperature has had a chance to equalise. Fish can't acclimate to the other parameters (pH, GH, KH) for weeks, sometimes never if they are very different to those in which the fish evolve, so I see no benefit to it.
Wouldn't drip acclimation not only be counterproductive, but more likely to kill your fish if this was the case?
 

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