For context. It's a 700 gallon outdoor pond in South Texas with probably about a dozen kois, 1 about a foot and a half and the rest about half his size or less. Pond was heated during the recent snowstorm.

I saw pinecone on this and another koi about 2 weeks ago, started Koi Prazi treatment a couple days later. The other one shows some improvement and it's swimming and eating more now but this one seeme to be a goner. Any idea which parasite is it and how can I treat it besides Koi Prazi? It looks like a 2-inch long red worm hanging off the wound

Update on my comet - Her butt has dropped and she's leveled out. No pineconing! Lots of poops, and circles around her tank. Will keep her inside for another week to monitor her and continue with daily water changes. I haven't salted her yet, as I'm waiting on some supplies still to make sure I do it right. I also am waiting on the antibiotics still.

Idk its Natural but my black koi has two white little scales missing im not sure if he’s sick or anything can someone give me a little insight?

So about 2-3 years ago, I was a stupid fish keeper that wanted koi. I got two little ones from Petco. I have had them in a 160 gallon stock tank in my basement since I got them. One died a year ago and now it’s the one koi with a few comet goldfish. The fish is now almost 11” and I need either to get rid of it or build it a pond this upcoming spring. I have no knowlege on outdoor ponds, so a baisic estimation on how many gallons it would have to be would be great. Also, I live in Hayward, WI; so it does freeze in the winter, therefore I also need a gas-exchange situation. Can you keep them alone?

Thanks;

Sincerely, a stupid fish keeper 👍

I've been wanting to get into keeping a Koi or 2 , i know they need large aquariums/ponds, but does anyone have any recommendations for small koi species, and good tank specifics for them. I live in Florida so idk about an outside pond. Any help is appreciated

Hi all. My pump at the bottom of the pond stopped working so I don’t have water running through the filter and out the waterfall. I am in NY so most of the top layer is frozen, with about 1/4 of the ice open due to the de-icer/warmer. So without water running through the pump I assume this is preventing oxygen? I wanted to wait to get another pump until it warms up and I can access the areas not currently covered by ice. Can I wait or should I get some sort of aerator for the time being?

I was going to get this for now:

https://a.co/d/g0bKged

She has looked like this for a month or so maybe? She has no issues swimming or with boiancy, her but seems lifted but otherwise, fine. It's winter so I haven't fed them in awhile. Is she pregnant or sick? I've never dealt with dropsy, so I'm totally out of my arena here. Any help is welcome. Thanks.

I am a delivery driver in a north east state. It has been very cold here with on and off snow. I deliver to a house with a koi pond. There was no waterfall or water movement in the pond.

I noticed that the fish were all just standstill in different spots, not moving at all. They were low in the pond but not tipped over or laying flat on the ground. When I first noticed them, there was no ice in the water because it was a warmer day.

Another time I went there shortly after, it had a cover of thick ice on top with no water movement.

The following time after that when it defrosted, I noticed the fish were in the exact same spots as before with no movement still.

Today the pond had a layer of ice again.

Are they hibernating or dead? I am concerned. I read there has to be water movement or a heater in the winter. I don’t know much. They were beautiful fish.

As per my last post in this group, we moved into this house on Saturday (1/18/25) and it came with a small koi pond. We estimate there's about 300 gallons of water in it. We had thought an owl got the fish (1 koi, 2 goldfish) but we have since seen the 2 goldfish hiding under the leaves at the bottom. So now we're trying to get the pond to a baseline healthy quality to keep them safe until we can expand the pond in spring. As some of you suggested, I got the API pond water quality test kit and ran those this morning, and they were bad. The Ph was normal at 7.5, but the Ammonia was 8.0, the Nitrite at 1.0, and the Phsophate at 10.0. I got some API Ammo Lock for the ammonia issue, and will be clearing out all the dead leaves from the pond today. I know that I should also be doing water changes, at 25% every 2 days to help woth the nitrite and phosphate issues. However, the water level is already lower in the pond, so I need to add water to it anyway. Would that be considered the first 25% change, and then I can do further changes after that? I also picked up some API pond chlorine and heavy metal neutralizer, am I able to add that directly to the pond after topping it off, or do I need to mix it in the new water before adding it in? I know I have my work cut out for me with this, the pond has been mildly neglected for a while, I think the previous owners fed them and that was pretty much it.

Hi, I know very little about koi, but this is a pond that’s in a building I frequent, and I just wanted to know if this is a safe and healthy pond for koi? Especially with the fountain running 24/7, does the sound of the water falling on the surface hurt the fish at all? Would really appreciate some insight. Mahalo!

Got these guys from Petco last summer. I’m thinking the 2 smaller guys are goldfish and not koi. What do you all think? And do they appear to be healthy?

I’m wondering what I can do to help my pond and koi recover from the wildfires? We weren’t in the fire zone but have had terrible air quality for the last two weeks. My concern is how much ash was in my pond and how it is impacting them. Is there anything I can do?

My friend Michelle works for the pasadena humane society and reached out to me. They have run out of room for koi being rescued from the fires. And need people to foster and or adopt koi fish. If you have room to help please contact the Pasadena Humane society.(626) 792-7151

A heron hit our pond here in St. Louis, MO. I spotted it outside with a 6" goldfish in its beak. I mean outside and scared it off. It dropped the goldfish in the snow, and I was able to inspect it. It seemed completely unharmed, so I tossed it back into our pond. It quickly scampered back to the cave. Looking over the pond, I spotted one other goldfish floating. It is still swimming, but it has 3 serious puncture wounds. I'm giving it a chance before euthanizing it with clove oil. The worst is our koi. I saw our 24" gold koi lying on its side in our cave. It's still moving around, so I haven't pulled it out to inspect since to didn't want to stress it. I fear it got stabbed also. If it got stabbed, is it worthwhile to put it in a hospital pool indoors where it's warm with pond salts and antibiotics to see it it can heal? Or is it doomed? That heron has now visited our pond every hour the last few days. I'm obsessively watching and chasing it off, but it keeps coming back. It's hard to see in this pic, but you can see Sunny the koi half in her cave. Easier to spot is the goldfish. After 3 days, it's still swimming around.

This is a great story.

https://www.nytimes.com/2025/01/20/realestate/los-angeles-wildfires-koi-rescue.html

*Devastating update: an owl took all three of the fish tonight. So I guess now I'm looking for advice on rebuilding the pond to be better.

https://imgur.com/a/WhM1s8M

This is what it looks like now, left to us by the previous owner. I'll be visiting a local water garden shop to browse and get information and pricing, but tips and tricks will be appreciated.

---------------------------original post-----------------------------

I've never posted on reddit before, but we need help, so here we go. So we just bought a new house that came with a (very small) Koi pond and 3 fish. The sellers showed us how muh they were feeding them (API Goldfish Flakes) twice a day, but otherwise, they didn't provide us with any information. We've never owned Koi before, so we're kind of at a loss. I've read conflicting sources on winter feeding. Some say that you shouldn't feed the fish at all when it's under 50 degrees Fahrenheit, others say to switch to an easily digestible food. There's a heater in the pond, but no aerator, and no thermometer to track water temperature. Any advice you can give on proper care and brand recommendations for aerators, food, and pond thermometers would be greatly appreciated. Would a normal pool thermkmeter be okay in the meantime? Should I keep feeding them, they didnt seem interested in the flakes yesterday morning? It wouldn't let me upload photos for some reason.

I do not know how many gallons it is but it’s about 7-8 feet deep pond and is probably 2000-2500 gallons. We have about 14 koi inside the pond, mostly 7 years or younger. The power went out 2 hours ago and the power will not turn back on for another 8. It is cold at about 40 degrees F too. It’s currently 0200 and no koi shop opens until 10:00am. My main concern is if my Koi will survive until the power kicks back on. Thank you for reading this-