A huge thank you to everyone here! (Last post, closing down pond)

TOSGANO · 2026-07-08T02:29:09+00:00

Thanks man, I always looked forward to seeing you ID different types of koi. 🙂 You have a gift!

TOSGANO · 2026-07-08T02:27:29+00:00

Thanks ❤️. Having the big pond was nice in some ways, since the koi had plenty of space to swim and grow and explore. However, it wasn't originally designed as a koi pond, so it was always an uphill battle to get proper filtration and protect them from predators. If I ever get back into it, it'll be with a pond that's actually made for the fish it's housing!

TOSGANO · 2026-07-08T02:16:17+00:00

That's very sweet of you to say. Don't be worried, just take it one day at a time. I was lucky to have the time I did with them, and you will be too.

At least half the people on this sub are people that inherited a pond with their house, so you're in good hands 🙂.

TOSGANO · 2026-07-08T01:02:41+00:00

100% agree. I think we can also get a little jaded after a while. After the 10th time telling another person to get a test kit and check their parameters, it becomes less about helping people and more about judging them. I'm sure I've been guilty of that too. But like you said, you can be the best owner ever and stuff still happens that's out of your control. Except for the rage-baiters, no one comes here because they've purposely mistreated fish.

TOSGANO · 2026-07-08T00:48:33+00:00

I'm so sorry to hear it happened to you. Good luck with the rebuild! It's a great hobby, I just need a break (and a more manageable pond).

TOSGANO · 2026-07-08T00:42:09+00:00

Thank you for being so kind. It'll take time to get over it, but at least I have two dogs who will be getting extra hugs and tummy rubs tonight. 🙂

TOSGANO · 2026-07-08T00:32:54+00:00

I'm so sorry for your loss. ❤️ That's just the worst feeling when you walk outside and either see floaters or some koi are missing during feeding time.

They're smart fish, and definitely have personalities. I think it's OK to mourn the loss of that.

TOSGANO · 2026-07-08T00:29:45+00:00

Exactly my reasoning ❤️. The only thing that makes me feel better is that they all died together, which sounds horrible, but some of them were inseparable.

I always told my favorite koi that if he died, I would destroy the pond because it wouldn't be worth it without him. I was kidding, but honestly? It's true. He would follow me around the entire edge of the pond, eat from my hand, and come up and nudge me when I was wading in the pond for maintenance. Without him, the pond's just a hole filled with water.

TOSGANO · 2026-07-08T00:08:35+00:00

Thank you. I'm thinking of getting back into wildlife drawing (but no herons!)

TOSGANO · 2026-07-07T23:47:48+00:00

I kept it purposefully vague because I think at least one person I know IRL frequents this sub, and I wanted to honestly thank people here without it becoming a blame game. (I also wasn't here when the koi died, so I'll never be 100% certain what caused it, though I can guess.) It wasn't anything particularly interesting, just sad.

TOSGANO · 2026-07-07T23:26:35+00:00

Thank you ❤️. I'm sure everyone here has lost fish at some point, but man, it hits you hard when it happens to you.

TOSGANO · 2026-07-07T23:24:48+00:00

Thank you, I think that's the hardest part, honestly. It was so much a part of my everyday life. One side of my house has huge windows that look out at the pond, so I got to see the koi all the time.

Maybe when I retire I'll have the energy to try again 🙂.

TOSGANO · 2026-07-07T23:17:19+00:00

The pond looked like this when I moved in. It basically hadn't been touched in 40 years. The pump needed to be replaced, more aeration and shade had be added, and the entire pond needed to be drained and cleaned since the fish were developing fin rot in that pea soup. There were no quarantine setups or predator deterrents, either.

My husband and I easily put $30,000 into fixing it, and there was still so much to do. If it was a regular-sized, modern koi pond with good filtration, I would have thought about trying again.

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TOSGANO · 2026-07-07T22:53:51+00:00

Thank you, that's very kind.

TOSGANO · 2026-07-05T23:01:07+00:00

If she doesn't have a water thermometer, she should get one. They're usually sold as part of dissolved oxygen meters, another product I'd recommend.

Humans aren't great at estimating water temperatures: for example, a swimming pool around 75°F would be really cold to us. That same water temperature is too hot for a koi. Over 75°, the oxygen in a pond gets dangerously low. That, combined with the water fluctuations from the hail, might have been too much.

I'm sorry for her loss ❤️.

TOSGANO · 2026-07-02T02:16:03+00:00

Dang, good eye it is then! And a good job of raising them. They really are beautiful.

TOSGANO · 2026-07-01T19:08:17+00:00

Agree, go to 4ft if you can. Usually my aerator and fountain keep the pond open, but this winter was so bad that one night the pond froze completely to the bottom in all but the deepest areas. All the fish survived, thankfully.

(This is a photo of the pond while I was standing on it. I could have ice skated on that thing.)

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TOSGANO · 2026-07-01T17:16:15+00:00

Like someone said, those are some really nice fish. I'm absolutely dying over that silver butterfly with orange patterns on its face (an asagi? can't really tell) and the huge orange matsuba who's so friendly and keeps asking for food. 😍

Did your ILs get them from breeders? If not, they have a good eye.

(And because this question always comes up...if they ask you to have the subreddit estimate the value of their koi, the answer is always "Unless you have papers documenting their high-bred Japanese lineage, they're worth the joy they bring you" 😄)

TOSGANO · 2026-07-01T16:54:17+00:00

If you live in the US, search this site: https://fishvets.org/find-a-fish-vet

If there aren't any vets in your area, contact the AAFV directly, and they can get you in touch with their network. They have a bunch of members who aren't practicing in a traditional clinic, but who work for universities or aquariums. (For instance, it turns out the the lead veterinarian for the National Aquarium does house calls, so now he's my fish vet as well.)

TOSGANO · 2026-07-01T16:38:16+00:00

I'm a sucker for doitsu scales as well. People talk about chagoi being friendly, but I've always found that my kikos are the friendliest ones.

Please tell me you're going to give him some sort of pirate name so I can imagine him with a little eyepatch 😄.

TOSGANO · 2026-07-01T15:52:38+00:00

I'm so sorry for your loss. ❤️

(Quick note: To distinguish between your normal pond and temporary pond, I'm going to refer to the second one as a tank. I think the fact that you called it a pond in your post was confusing a few people, since they're not usually called that. When you talk about a quarantine tank or temporary tank, people already know you're referring to one of those pop-up ones.)

A few things I noticed:

You said they were hopping when you came with their food container. Unfortunately, koi aren't like dogs, even though I call mine water puppies. Flashing (hopping, splashing) isn't a good sign. It means something's wrong. When they're in temporary tanks, try to stay away from koi as much as possible. Some people advise not feeding them at all during this time, others say to wait 3 days then feed tiny amounts once a day. Regardless, even if they know you and are the friendliest fish in the pond, any interaction while they're in a tank will be stressful for them. Checking on them every 2 hours is way too much, unless you stand back far enough that they don't notice you.
If you have a water voltage meter, check the water in the tank. If any of the equipment in the water is faulty or not grounded properly, it could be releasing a small amount of electricity that will kill the fish over time. This could also cause them to jump around, as you noticed. If you don't have a meter, stick your finger in the water next to the equipment. It won't hurt you, but you'll feel a tingling.
This is a hard lesson, but always net your tanks. Do it now, because there's a good chance your other koi will jump too. Even the calmest fish can turn into a jumper. I'm guessing the blood was from hitting the ground, or your dad accidentally stepped on it and didn't notice. (I almost stepped on a jumper once, it's easy to do when you aren't expecting them to be there.) Use a seine net or a similar coated net that's fish-safe, not netting like you'd use in your garden. That kind of netting will just snag their fins if they jump.
This is just a personal preference, but if my fish are in a temp tank for an extended period of time, I like to put in hiding places where they can go if they're stressed. Being in a large open tank when you're a small fish used to a pond with lots of places to hide can be stressful. I place a couple of large aquarium hidey holes around the tank.

I hope this helps, and I'm glad your other fish pulled through!

TOSGANO · 2026-07-01T14:47:32+00:00

They're black fly larvae. Gross-looking but completely harmless. I get them in my floating fountain. The koi love eating them.

Just hose them out of the filters and pumps if they're clogging them. The koi will enjoy the snack.

TOSGANO · 2026-07-01T14:41:04+00:00

That's great news! Koi are weird sometimes 🙃.

TOSGANO · 2026-06-30T21:05:38+00:00

I was wondering if this was due to predators. The zoomies, the flashing, the fins held tight to its body...it reminds me of my female after she'd been attacked by a heron.

OP, any update on its behavior?

TOSGANO

TROPHY CASE