culling fry with single tails

[Kulukan 204]

If a fry appears to have a single tail before they are 2 weeks old is it likely they truly have a single tail or is it possible that it's too soon to tell?

I just went through my fry and well over half appear to have single tails. I would rather cull now when they look less like fish than later (because it makes me feel kinda bad). Some of the same age are very clearly double tails (even though they are smaller). I just want a second opinion before I dump these guys back in my main tank.

[shakaho 6,312]

Single tails will stay single and double tails will stay double.

[GoldenSpoiledRotten 6,786]

Wait another 3 days and then see. You will definitely be able to tell the difference at the 2.5 week mark.

Instead of dumping them in the main tank, I would cull in another way. I learned the hard way that dumping these guys in doesn't necessarily mean they will be eaten, nor does it mean they won't wind up back in your container because they look like baby fish.

[4prettyfish 2,702]

No advice here for I've never had any fry. I just wanted to wish you the best during this time of decision making.

[Kulukan 204]

Single tails will stay single and double tails will stay double.

That's what I thought thanks they very clearly look like single tails.

Wait another 3 days and then see. You will definitely be able to tell the difference at the 2.5 week mark.

Instead of dumping them in the main tank, I would cull in another way. I learned the hard way that dumping these guys in doesn't necessarily mean they will be eaten, nor does it mean they won't wind up back in your container because they look like baby fish.

If they are crafty enough to survive to that point then they can go live in the pond thanks I've looked at them every which way and there is no way they have double tails right now. Edited July 28, 2014 by Kulukan

[Justin 383]

Wait another 3 days and then see. You will definitely be able to tell the difference at the 2.5 week mark.

Instead of dumping them in the main tank, I would cull in another way. I learned the hard way that dumping these guys in doesn't necessarily mean they will be eaten, nor does it mean they won't wind up back in your container because they look like baby fish.

What culling method would you recommend? What are the options?

[GoldenSpoiledRotten 6,786]

Wait another 3 days and then see. You will definitely be able to tell the difference at the 2.5 week mark.

Instead of dumping them in the main tank, I would cull in another way. I learned the hard way that dumping these guys in doesn't necessarily mean they will be eaten, nor does it mean they won't wind up back in your container because they look like baby fish.

What culling method would you recommend? What are the options?

The same way you euthanize adults, or freezing.

[Mikey 6,780]

I would prefer using the clove oil method as freezing is a slow and cold death. I think it's kind of cruel in my opinion... but that's just me. I would rather watch the fish in clove oil calmly and painlessly pass on than freeze to death in a freezer.

[shakaho 6,312]

There is a lot of current research indicating that rapid chilling is one of the most humane methods of euthanizing fish. Here is one source. This does not mean putting the fish in the freezer, but rather putting it in ice water which results in virtually instant unconsciousness. For goldfish, once the fish appears dead it should be frozen in the freezer because they can recover from chilling to 0 C.

It is interesting that while there are still some people who claim fish don't feel pain, there are others who insist fish feel pain that we don't, insisting that ice crystals forming in cells must be horribly painful. When and where I grew up, frostbite (frozen skin) was common, particularly in the toes. Temperatures were often below 0F, instead of warm winter boots, we wore rubber overshoes, and we had long rides on buses that were heated, but not above freezing. Every schoolteacher knew first aid for frostbite. The freezing doesn't hurt at all. Thawing is painful. That's how the teaching knew the child had frostbite -- "My toes hurt!"

As unpleasant as it may seem to us, I doubt tiny fry experience any pain from being eaten. Their nervous systems are barely developed. They seem to have two reflexive behaviors -- swim away from anything coming toward you and eat anything that fits in your mouth.

Here's another thing to consider. You rarely see nymphs in a pet store tank. This is because they can be recognized and culled almost from hatching and thus rarely survive to selling age. Yet most people find these fish very appealing, and they make better pond fish than twin-tailed fancies since they swim almost as fast as comets and can escape predators just as well. You might keep some and see how well they sell. "Nymphs" sounds appealing and exotic.

Edited July 28, 2014 by shakaho

[*Amanda* 556]

I had a single-tailed ranchu who was very hardy and survived longer than any fish I've had thus far. In his case, the single tail went horizontal (fully fused) instead of vertical. My boyfriend was drawn to him because of the single tail and white coloring. I also bought a telescope who has a fused upper caudal fin, and was attracted to her because of it. These fish won't win any awards, but a lot of people really like them.

[koko 14,335]

There is a lot of current research indicating that rapid chilling is one of the most humane methods of euthanizing fish. Here is one source. This does not mean putting the fish in the freezer, but rather putting it in ice water which results in virtually instant unconsciousness. For goldfish, once the fish appears dead it should be frozen in the freezer because they can recover from chilling to 0 C.

It is interesting that while there are still some people who claim fish don't feel pain, there are others who insist fish feel pain that we don't, insisting that ice crystals forming in cells must be horribly painful. When and where I grew up, frostbite (frozen skin) was common, particularly in the toes. Temperatures were often below 0F, instead of warm winter boots, we wore rubber overshoes, and we had long rides on buses that were heated, but not above freezing. Every schoolteacher knew first aid for frostbite. The freezing doesn't hurt at all. Thawing is painful. That's how the teaching knew the child had frostbite -- "My toes hurt!"

As unpleasant as it may seem to us, I doubt tiny fry experience any pain from being eaten. Their nervous systems are barely developed. They seem to have two reflexive behaviors -- swim away from anything coming toward you and eat anything that fits in your mouth.

Here's another thing to consider. You rarely see nymphs in a pet store tank. This is because they can be recognized and culled almost from hatching and thus rarely survive to selling age. Yet most people find these fish very appealing, and they make better pond fish than twin-tailed fancies since they swim almost as fast as comets and can escape predators just as well. You might keep some and see how well they sell. "Nymphs" sounds appealing and exotic.

Thank you....

[Chai 7,337]

These fish won't win any awards, but a lot of people really like them.

Absolutely!

[GoldenSpoiledRotten 6,786]

Sharon rocks. We all agree!

Well put.

I also love nymphs, if my signature is of any indication. Keeping some would be really neat.

[Glenn 32]

I read a scientific article on line and am trying to find it. The scientist used galvanic skin response to measure the amount of pain a goldfish feels with different methods of euthanasia. The least painful was clove oil in water, and the most painful was freezing. I'll keep looking for the article.

[GoldenSpoiledRotten 6,786]

I read a scientific article on line and am trying to find it. The scientist used galvanic skin response to measure the amount of pain a goldfish feels with different methods of euthanasia. The least painful was clove oil in water, and the most painful was freezing. I'll keep looking for the article.

Most people here use the clove oil method.

Also, this thread hasn't been posted in since July. It's old.

[koko 14,335]

I read a scientific article on line and am trying to find it. The scientist used galvanic skin response to measure the amount of pain a goldfish feels with different methods of euthanasia. The least painful was clove oil in water, and the most painful was freezing. I'll keep looking for the article.

Please do not post in threads that are over 3 months old..... only if they are pinned

[DieselPlower 2,123]

Why would people not want the results of a study that are directly related to a controversial topic posted in a thread that are only a few months old?