Question
Hi,

I have a smallish pond, (sorry I don't know exactly how big it is, but it was built for koi by someone a while ago so I know it's big enough.)

I want to have 2 or 3 koi in it. I have several questions about them.

First of all, I want to just let nature take it's course in terms of prediters, I have a fence around the pond but persistant preditors could get in. Therefore I can't afford the expensive koi from a breeder, they might get eaten. We have a petco thet sells koi, is there a big difference in the longevity, health, and hardiness of the koi, between breeder koi and petstore ones? Do petstore koi have enough of a chance of surviving a harsh winter like we have in Vermont, if the pond doesn't freeze?

My next question is, is there any way I can have koi without a filter? Do they need water circulation in order to breath? Or is a filter more important because of cleaning water? We're thinking of having a small solar powered water fountain, that would just run and provide circulation when the sun was out, but no filtration. Would that be okay for airating water if that's what koi need?

Next, how cold is the coldest koi can have? I know you can't let the pond freeze, but other than that, how cold can it get before they get sick? The winters where we live get down to -20 degrees Farenhight sometimes.

Next, if your pond has mosquito larvae and algea in it, can koi eat what they find and not need food from me? Would it be okay to make my own food if they did need food from me? If so, how would you make your own koi food?

Next, do you need to do water changes where you take out some of the ponds water and replace it? Or can I just replace any evaperated water?

Thanks in advance,
Miriam

Answer
Hi Miriam,

Thank you for contacting me.
Let me try to help.

I have a smallish pond, (sorry I don't know exactly how big it is, but it was built for koi by someone a while ago so I know it's big enough.)
I want to have 2 or 3 koi in it. I have several questions about them.

=> Knowing approximate how large the pond is would help in to how mutch koi you can keep.
Also to ensure they have sufficient water and safety a pond should be as minimum 1,5 meters deep (if there is a winter in your area).Then you can have (if you use nature filtering) maximum 1 koi per 5000 Liters.

First of all, I want to just let nature take it's course in terms of prediters, I have a fence around the pond but persistant preditors could get in. Therefore I can't afford the expensive koi from a breeder, they might get eaten. We have a petco thet sells koi, is there a big difference in the longevity, health, and hardiness of the koi, between breeder koi and petstore ones? Do petstore koi have enough of a chance of surviving a harsh winter like we have in Vermont, if the pond doesn't freeze?

=> There should be no difference in koi concerning breeders. Even so, sometimes when you get koi from a specific breeder and top class they tend to have even more nursery needs.
If the ponds are deep enough, and large enough you can keep koi safe in the winter.
Freezing over should even help during the winter or you need to cover the pond. When freezing over, you need however to add a small opening in the ice and remove some water so there is a natural aer isolation between ice and water and also the koi would not stick to the ice.

My next question is, is there any way I can have koi without a filter? Do they need water circulation in order to breath? Or is a filter more important because of cleaning water? We're thinking of having a small solar powered water fountain, that would just run and provide circulation when the sun was out, but no filtration. Would that be okay for airating water if that's what koi need?

=> good question! a pond needs to have sufficient material to filter the water and remove visible and invisible debris. So every ponds needs a filter and this depending on the amount and type of fish. Then you can choose. Natural filtering (with plants and substrate) or artifical with the professional filters.
Depending on this you need to have someone calculate how and wich pump would to the job to have the water circulating enough. Also, you need to have sufficient watermovement to Ensure there is enough oxigene in the pond for the koi.

Next, how cold is the coldest koi can have? I know you can't let the pond freeze, but other than that, how cold can it get before they get sick? The winters where we live get down to -20 degrees Farenhight sometimes.

=> normally a koi can have approx 7癈. so I guess you need to cover the pond and keep it out of the cold winds. Freezing over is not that bad as you keep my advise as above.

Next, if your pond has mosquito larvae and algea in it, can koi eat what they find and not need food from me? Would it be okay to make my own food if they did need food from me? If so, how would you make your own koi food?
=> If you want to keep koi healthy I would give some extra food. You can make it yourself or buy it in the store. Homemade i use mostely brown bread, Mais, paprika, oranges, latice...

Next, do you need to do water changes where you take out some of the ponds water and replace it? Or can I just replace any evaperated water?
=> Most koipond owners change weekly 10 procent of the pondwater.
This will reduce ammonia, nitrate and nitrite and will add new and fresh spore elements etc.

Hope this helps out a litle.
If you need more help, do not hessitate to contact me again.
Or you will be welcome on many websites with fora to ask questions.
So good luck and happy koikeeping!

Kind regards,
Raf
Belgium