Too many fish too fast...need advice.


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Okay so I am going to start this thread in part for myself and in part for others to learn from and hear all the reasons why not to do what I am about to do I one thread. I am hoping for some of the pros to weigh in and offer constructive advice along with the anticipated and deserved criticism.

Quick rundown of the situation
We made some friends that found themselves in a difficult situation. The have a pond about the same size as ours. I don't know their filtration setup just yet but I will. They are 4 days from having to be out of their house since they sold it and are purchasing another home. They tried selling all of their koi before moving. Unfortunately they could not, so they offered to sell the rest of them to us for a really good price.

Here is the problem
Our pond is new, possibly (though I don't think so in the pre-cycle phase. It has been up and running for just over a month now. We bought 12 koi from them averaging about 14 to 16 inches each a few smaller 8 to 10" ones. Now that they are 4 days from closing they offered the remaining 15 koi that they could not sell for another really good price all around the same size with a couple that are over 16"s.

Our pond is not ready to take on this load, nor was I really but my wife got excited and caught up in the moment and here we are with around 25 koi going in our pond. We have had the 1st 12 for about a week now and the ammonia levels have stayed flat.and the water is clearing from a brown algae phase. So current water conditions are spot on.

I don't want to have this many koi so this is a temporary situation and we will be selling about 10 of them. But until then I need some of the pros to post up their trade secrets for such a situation.

Pond details for those that have not followed my build thread. It is abour a 15,000 gal pond with an EPDM liner and a rocked bottom. It has a bottom drain which will be connected by the end of next week that will flow to a biological media filled waterfall spillway for areation, powered by a 12.5k gph pump. But do to the height of the lift about 16 feet it will likely flow much less. The pond currently has a 55gal skimmer that sends water to an upflow bog filter that is currently about a 4th the size of the pond at 1- 2k gph. We have a few plants in the pond as well and plan to add more and add another bog about the same surface space as the current bog. Lastly we plan to use add wetland pockets around the pond where we have a lot of excess liner.

-The current plan is execute the rest of the build within a week ie the waterfall, 2nd bog and planted wetland pockets.
-Add 64oz of stress coat
-Monitor the ammonia levels
-Hide the fish food from my wife
-Feed the fish minimally
-add more plants in the pond
Sell 10 of them as fast as possible

What else can I do to maintain water quality and fish comfort?

Also one of my fish did spawn so we had not been feeding them much less than once a day.

Here is another question, I know (now thanks to the great advice of this forum) when fish spawn to stop feeding them. But here is my question in a newly established pond is there enough growing to sustain them?
 
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25 koi in 15K gallons - it could be worse. All the fish coming from the same pond - it could be worse. Pond's been running for a month - it could be worse. All thing's considered - it could be worse.

I would feed them with a light hand. They're stressed as it is - at least give them something to look forward to. And you're right - that's a lot of big koi in a new pond. They'll eat your plants if you don't feed them something!
 
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I agree, it could be worse - ha ! I do think you need to turn more water over if the pond is 15,000 and your pump is pushing less then 12.5. It should turn over AT LEAST once and hour and closer to two is better:)

Also I would not depend on the drop from your waterfall for your complete aeration needs. I'd add an aerator, or will your bottom drain be aerated?

Is the bog serving as your mechanical filtration? Koi create a good bit of waste.
 
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You should be able to determine your water flow from the technical data on the pump in the instructions or on line. You have 16 feet of head plus the friction head in your plumbing running to the top. I’m guessing that the total is approximately 22 feet of head without knowing the details. That probably drops your flow to around 7500 gph. just guessing.

It would be hard to see why you will have any problems with this school. We temporarily housed our 50 fish for maybe 10 weeks. No problems. We water changed a lot. Feeding is out except for maintenance. We didn’t feed for 3 weeks at one point but then again our fish were fat.
 
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I agree, it could be worse - ha ! I do think you need to turn more water over if the pond is 15,000 and your pump is pushing less then 12.5. It should turn over AT LEAST once and hour and closer to two is better:)

Also I would not depend on the drop from your waterfall for your complete aeration needs. I'd add an aerator, or will your bottom drain be aerated?

Is the bog serving as your mechanical filtration? Koi create a good bit of waste.
I was thinking a separate form of aeration would be a good idea. Currently yes as the bottom drain is not hooked up yet. I do plan to design the waterfall spill way to house additional mechanical filtration since it will pull from the bottom drain. The 12.5 is just one of the 2 pumps the skimmer pump is 2.5 and I will be adding (since it was gifted to me with the fish another 1.5k pump through the secondary bog.
 
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You should be able to determine your water flow from the technical data on the pump in the instructions or on line. You have 16 feet of head plus the friction head in your plumbing running to the top. I’m guessing that the total is approximately 22 feet of head without knowing the details. That probably drops your flow to around 7500 gph. just guessing.

It would be hard to see why you will have any problems with this school. We temporarily housed our 50 fish for maybe 10 weeks. No problems. We water changed a lot. Feeding is out except for maintenance. We didn’t feed for 3 weeks at one point but then again our fish were fat.
Thank you, the weather here has been hot so I top off the water l about every other day and the sprinkler hits it daily too which also creates a little aeration I would imagine, and the bog has a mini falls which creates so.e aeration too. Key here is not letting my wife feed them so much.
 

addy1

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At least you are aware of the potential of issues! I would follow the advice above. Feed light add air, test test test the water.
Add new water every day.
 

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go to garden centers and put up posts I did that and got a list of people who want fish.Did you manage to hide the food from the wife ,hiding things from women never really works ,you know .Quilt batting in a crate will help and with ammonia you can get zeolite and gets some koi clay .It will cloud up the water but after a day or 2 you will see a big difference
 
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Craig'slist and Facebook for sure. Not so much here because I would lot know the first thing about shipping them.
I was thinking from the standpoint of someone on here might live close enough to you... Yea, shipping would just make a bigger headache. I liked Sissy's suggestion, of posting at garden centers (if available). Maybe even local pet stores, pond suppliers, or my favorite way to get rid of things, the community board at Tractor Supply! Anyway, good luck - I'd hate it for you, after you've worked so hard on your amazing pond, to have things crash on you.
 
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I agree, it could be worse - ha ! I do think you need to turn more water over if the pond is 15,000 and your pump is pushing less then 12.5. It should turn over AT LEAST once and hour and closer to two is better:)

Also I would not depend on the drop from your waterfall for your complete aeration needs. I'd add an aerator, or will your bottom drain be aerated?

Is the bog serving as your mechanical filtration? Koi create a good bit of waste.
This exactly!
If you don't have a pond aerator I would look into getting one, koi need a lot of oxygen....also the bog is great, but once the plants start to dye off if your water quality struggles you need to consider regular water changes until you lower the number of fish
 
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You need to replace some of the water, topping off allows the bad stuff in the water to get worse, if your tests start to climb.
True I am thinking 10% water changes daily if I see a noticeable change in the ammonia.
I was thinking from the standpoint of someone on here might live close enough to you... Yea, shipping would just make a bigger headache. I liked Sissy's suggestion, of posting at garden centers (if available). Maybe even local pet stores, pond suppliers, or my favorite way to get rid of things, the community board at Tractor Supply! Anyway, good luck - I'd hate it for you, after you've worked so hard on your amazing pond, to have things crash on you.
All great ideas thank you and @sissy. That was my fear that I just could not communicate well enough in the moment but I think we can make this work.
This exactly!
If you don't have a pond aerator I would look into getting one, koi need a lot of oxygen....also the bog is great, but once the plants start to dye off if your water quality struggles you need to consider regular water changes until you lower the number of fish
True and I was wondering this I will ask here as I did in another thread. Would a winter filter (mechanical in nature and possibly heated) be a good idea in this case?
 
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I don't run my filter in the coldest part of winter, due to my set up. I run a Pond Breather and an aerator.
 
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True and I was wondering this I will ask here as I did in another thread. Would a winter filter (mechanical in nature and possibly heated) be a good idea in this case?
Pond keepers are not all in agreement when it comes to winter ponding, some shut down everything and move airline higher trying not to disturb the warmer water at the bottom where the fish lay, I believe that aeration and oxygenation are more important than keeping the water a few degree warmer.
I never used a heater, my Pond Max 40 aerator does a great job keeping an opening in the ice.
I leave everything running 24/7, 365 days, unless the waterfalls builds up ice too fast and starve the pump, then I turn pump off but usually for very short time.
 
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Would a winter filter (mechanical in nature and possibly heated) be a good idea in this case?
I'm not sure this was a winter pond question or a question of using winter equipment now to add aeration - what exactly is a "winter filter"? I'm not familiar with the concept of a heated filter for winter.
 
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My converted swimming pool pond is 15k gallons as well. In the past I have had close to 40 koi and at least that many full grown goldfish. They did fine for a number of years until the koi got too big for the filtration system I think. The main difference I can see between my system and yours is the pump. I'm running a 7500 gph pump driving an AquaUltraviolet filter rated for up to 20k gal.
So you might look into a larger capacity pump. They aren't cheap, but once you got it you got it. If you are able to off some of the fish you should be fine.
 
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True I am thinking 10% water changes daily if I see a noticeable change in the ammonia.

All great ideas thank you and @sissy. That was my fear that I just could not communicate well enough in the moment but I think we can make this work.


True and I was wondering this I will ask here as I did in another thread. Would a winter filter (mechanical in nature and possibly heated) be a good idea in this case?
10 percent daily change is way too high. The standard is 10 percent a week. The whole purpose of a water change is to reduce the dissolved organic compounds that will build up and are evident when your waterfalls begin to foam and the foam is persistent. If you think about it, the only materials that can build up are chemical waste, solid waste and dissolved organics. Filters take care of the first two and water changes and foam fractionators take care of the organics. Use a fractionator instead of massive water changes, or set up a continuous exchange system like the one we use. Since our pond water is pumped from a lake and is ridiculously cheap, we set up a fill line running off the irrigation system. Every time the irrigation system runs, water is added to the pond. With our leaks that probably lose 3/4 inch a day, we replace probably 5 inches a week, and that is about 12 percent.
 

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