is the tank too small????

the fish i am looking to buy that get to about 7 inches need at least a 100 gallon tank, sometimes even bigger

not sure if that applies to koi and aquariums, but when my larger fish/koi in my pond get spooked, they shoot across the pond. Basically they go at least 6 feet within about a second. and that distance in a tank, they will likely hit the wall

I never worked with Pavlov or those other guys with behavior and conditioning, but i am assuming the pain when he hits the sides of the tank is associated with you. so everytime he sees you, he freaks out even more and gets even more negative reinforcement

Koi and goldfish need lots of room. Koi and fancy goldfish should not be kept together. The fancy goldfish are just to slow.....the single tail goldfish and Koi are much faster.

Now having said that......when fish freak there is usually a reason. Check the water quality.....thats the first sign of poor water quality. What is the temp? Koi and goldfish like cooler temps....high temps can make them uncomfortable and freaky.

You will need 30 gallons of water for each fancy goldfish and more for single tailed goldfish and koi. Do you have good filtration in this tank? Are you doing weekly or twice weekly water changes? Koi and goldfish polute the tank very quickly. What are you feeding and how much....over feeding can pollute the tank very quickly.

Healthy Koi and goldfish will come out to the front of the tank when you walk into the room ...expecting to be fed....they are peaceful fish.

Sierra

well i know that the tank is a little small, but they go outside as soon as it warms up. its a 55ish tank. and the 7incher is the largest fish in the tank.the other koi are only 3-4 inches. what i find strange about this whole thing is that its just been the past few weeks they've been acting weird. and its only the koi. the tetras, barbs, and ciclid are all friendly and happy and come to the surface to eat and are being normal. the large koi concerns me.
beanie... i thought about that...that maybe i was scaring him/her but we've not done anything different since we've had him/her and that's been since new yearsish. the other small koi we've had since the summer and they all acted normal too.
i do have a heater in there... maybe that has to do with it. without a heater the temp is usually about 72-74. right now its 75-76. i raised it a few degrees because of the other fish. i wouldn't think that 2 degrees would make that big of a difference. course what do i know... i've got phsyco koi. I have a fancy goldfish that i've had for nearly a year and he's got a heater in his tank and it stays 76 all the time. he doesn't freak out when i come around.
i don't know what i'm doing wrong.
Bri

what other fish do you have in this tank?

My koi pond had been raided the first few years by raccoons - relentlessly until I figured out how to work something out to keep the raccoons out (design, a device called the Scarecrow) - but because of this, the surviving fish are rather wild. They come up for food, but otherwise usually scoot when they see movement. It could be that something is spooking your koi - but I'm also wondering if in fact the water is just too high. Koi are coldwater fish - and warmer waters may spur spawning. Is your koi female by any chance? Do you know the sex of the koi?

i'm not sure i'll look up how to tell their sex and see what i get. I can sex fancy goldfish but thats not particularly hard to do. could be that its being territorial with the other fish if its looking for a mate? what is a good temp that i can keep it at first all the fish so that its comfortable with out being to cold for the tropicals...
i'm hoping to be able to put him/her out by first of march. we're in TN so march is cool without freezing and my pond is a 90 gal above ground so...
Bri

It has nothing to do with being territorial. When Koi spawn, they get extremely active. I do want to warn you that keeping Koi in 90 gallons is going to be tough. Koi like space and during spawning season they sometimes leap out of the water. Essentially male kois will chase female kois relentlessly while forcing them against walls and objects to get the females to eject the eggs so the males can fertilize them.

In TN - if you have raccoons, a 90 gallon above ground pond will be feasting grounds. (I've been there, so I know!)

Also - above ground fish usually wind up having to come indoors in the winter because of freezing issues. Do consider all of this before you set up your pond. Plan now so you're not scrambling later on.

Koi truly are cold water fish. They can survive in water iced over (as long as there's an opening in the ice for gas exchange and as long as the depth is more than 2 feet). They tend to get stressed in warm water conditions - and some folks in really hot parts of the country have a hard time keeping their small ponds cool enough to keep koi in the summer.

Sexing Koi is fairly easy. It's the shape. If they're long and narrow, they're male. If they're somewhat rounder and fuller bodied, they're female.

Certain parasites may also cause fish to flash.

Fancy goldfish need warmer temps - which is why they generally are not kept with Koi. They move more slowly and sharing space with Koi usually mean they don't get their share of food.

Your gold fish may have some kind of parasite which causes them to "flash" or freak out there trying to get the bugs off. Contact your local pet store and ask about solutions. A salt water dip or other medications will do the trick but get info on this before doing it.