Added a few koi to a established goldfish pond

[anthony21078]

My kids have been bugging me ever since building my pond that they wanted colorful koi. I was always concerned with overpopulating the pond and I didn't want to add koi after already having goldfish.

Nevertheless, I fell victim to the sad faces and we picked up a few koi and the kids are happy. Ive lost quite a few goldfish over the years to prey and the population was shrinking. I am concerned about the bioload but I feel like I have good filtration and plenty of plants.

My question is about feeding the koi. When I first started the pond I was feeding the goldfish everyday. Over time I learned they will eat almost anything in the pond and now I was feeding every 4-5 days.

The koi farm we went to was very friendly, helpful and gave a lot of advice. I know they're tank setups are much different with heavy filtration compared to residential owner but they were recommending at least two to three times a day for feeding.

I suppose from their point of view there's nothing wrong with it and it will help koi grow bigger much faster. But from a homeowners point of view I could see the bio load from so much waste increasing exponentially and just causing problems.

Is there any reason I should be feeding the koi more often than I was originally feeding my goldfish?

 

[mrsclem]

If I remember correctly, your pond is under 1000 gallons. How many koi did you get? Feeding multiple times a day will get you some very large koi very fast and very poor water quality as well. I sold koi for years, had several go 36" and larger and had several filters that required daily cleaning. Check out Shubunkins, colorful and think your kids will like them. See if you can exchange the koi - unless you are planning digging a larger pond!

 

[Tula]

I feed my koi once a day

 

[Mmathis]

How big is your pond? I don’t have koi, but I rarely feed my goldfish.

 

[Mayank]

I feed my koi/comet mix once a day max but if its raining or I'm out of town, I don't care if they go for a few days without food. I bet they do just fine on algae etc. I feed them only my home made veggie food. I use a small container (a tiny metal bowl) and try not to give them more even if they're begging for more.

So what do you'll think of my homemade koi/goldfish food?

OK be nice :) . This is my first attempt. We do have some store bought koi food but it has corn like a lot of them do and I was told to try and avoid it by my pond place. So I thought I would come up with a recipe of my own to make food for my little scaly friends. So here went nothing :D. I...

www.gardenpondforum.com

 

[anthony21078]

My pond is 1000 gal give or take 100. 2 large box filters on the floor and filter pads in the skimmer and waterfall box. I rotate the cleaning of pads quite often and recently added more plants (maybe 10 or 11 total) that have grown quite well the past month. Deep root growth through the rocks.

I have 2 shubunkins and a few 2" comets. Will likely get rid of the comets and stick with koi.

I am likely overstocked and maybe I'm wrong but I think my filtration is adequate for the amount of fish. If not, maybe another filter box, more plants, less feeding. If none of the above work, time to rehome some fish.

I'll feed once a day, taking a day or 2 off each week here and there for the rest of the summer

 

[brokensword]

Be sure the kids are there when problems arise (and fish start dying) due to your filters being overwhelmed, which WILL happen. @Lisak1 has a chart showing how the output from koi goes up exponentially with growth. It's eye opening. The kids are going to be a lot sadder when that happens than when you exchange them for Shubunkins. Not trying to do anything but warn you; 1000 gal is not enough for more than one mature koi.

 

[Mmathis]

@brokensword Harsh, but well-said!

 

[Lisak1]

Here you go:

Koi Length and Weight - Ammonia Produced, and Waste Produced

This chart also lists koi weight by weight and how much ammonia and waste they produce. Koi get heavier as they grow and produce more ammonia and waste.

russellwatergardens.com

@brokensword is correct. There is nothing sadder in pondkeeping than losing fish. This would be a good opportunity to teach your kids the importance of making sure the animals in your care have the type of environment they need to be healthy. Just like you wouldn't bring a pony home and raise it in your living room, you can't keep koi in a too small pond and hope for the best. The inevitable will happen. You might get three, four, five years of "all is well". But we hear ALL THE TIME "I've had this pond for years and everything has been great... and now my fish are all dying!"

CAN you over filter a pond and keep it overstocked? Sure. But when will you know that it's not working? By the time you see the signs, it's too late.

Check the chart I shared and show your kids the math - the difference between on 12 inch koi and 4 three inch goldfish is remarkable.

 

[SarahT]

In my 900 gallon pond, I had a single koi (he was a 7" baby when I got him) and some goldfish, fed once a day at most, but I usually skipped a day or two a week [ someone can insert sad little fish faces emoji here] in the summertime, and didn't feed them at all under 60 degrees (water temp) and they did fine for many years. But, I would not have added another koi, as keeping the water quality under control was increasingly difficult. (We moved to FL and they're in a bigger pond, my solution to the growing koi. So far we're all well.)

 

[brokensword]

@brokensword Harsh, but well-said!

yeah, but I figure the kids will survive; the fish won't.

 

[anthony21078]

Okay I appreciate all the advice I really do. I get it. A lot of you have much more experience than I do and your opinions are likely based on facts. But surely there has to be people out there that overstock ponds and don't have problems. So like it was said above that you can have over-filter an over-stocked pond, are there any suggestions to increase filtration besides loading up the entire bottom of my pond with box filters?

I would think a bog mighy be my best answer to greatly increase filtration. But, if I'm going to build a bog I might as well increase the pond size. I have plenty of room for both but it's a big project and would like to explore other options. I have plenty of room around the back side of my pond where I could create a small wall to hide a another large above ground filter box and pump. Maybe add 3000gph pump?

Right now I have a 1500gph pump for the waterfall/skimmer and a 1000gph pump for the box filters.

 

[brokensword]

that's the key; have a BIG pond and overstocking gets a lot harder to do and a lot easier to forgive. It's the small natured pond that tends to create all the problems and gets snarky responses from the likes of me. We want you to enjoy the pond, we want you to have fun, we want you to brag how good your fish look; we just want to insure they're not floating when you do.

Small ponds = goldfish. Large pond = koi and/or goldfish. A bog will give you a lot of latitude for success but you still need adequate volume and surface area to keep koi. Ask anyone here who's seen my vids; they'll tell you I'M overstocked. To which I'll nod vigorously and say; get your popcorn, sit down, and hold my beer!

 

[cas]

My pond is about the size of yours. I also have goldfish and a few koi. I only feed my fish daily and don't worry if I miss a few days.

Enjoy your new fish and be aware you may need to make some adjustments later, if the koi do end up getting large. My 12 and 15 year old koi are only 12", but I am still trying to catch some goldfish to give away to make room in the pond.

 

[Lisak1]

you can have over-filter an over-stocked pond,

If you choose to go this route, be aware that you will also need to closely monitor water quality. Things can go upside down very quickly.

I'm not sure what you mean by "box filter" - can you explain what those are?

The filtration you need to increase is the biological filtration - mechanical filtration is important but isn't the critical factor. A bog will add biological filtration, as will plants in the pond. The filter pads in your skimmer and waterfall will add to the biological filtration IF you're handling them correctly (specifically NOT rinsing with chlorinated water). However, the only way to know for sure if you're at the right level of filtration is water testing. Keeping a very careful eye on what's going on with the water will be most important. And knowing what to do if something goes wrong.