View Full Version : Baby Koi

06-05-2007, 10:56 PM
How big should baby koi be after one month?

Will having 300 or so in a 75 gallon tank stunt thier growth?

06-06-2007, 07:47 AM
300 in a 75 gallon tank would definitely stunt them unless you are doing constant water changes and turning the water over at a rate of at least 100% per day.
If I was you I'd cull the runts and physically defective ones now to thin the herd to a more manageable number. Give them 2 weeks, decide what type you are most likely to have success with, and cull anything that doesn't fit the description.
How big are they now, what parents do you have, (variety and size descriptions please), and how often to you change water and feed?

06-06-2007, 10:07 AM
They are about 3/8 inch now. I am not sure who their parents are but I have domestic koi. My adults range from the 5 year old at 18" to a two year old at 8". I have a total of 18 adults. I have not done a water change regularly. They are eating 3 times a day and I am feeding them ground up adult food. They also have algae in the tank. I have an air stone in the tank not a pump. I am not sure if the water is being turned over at a rate of 100% a day. I don't think that it is.

06-06-2007, 12:21 PM
By turned over I don't mean filtered, I mean completely replaced with dechlorinated water!
Lots of aeration is good, and quite likely the only reason they are still alive, but their growth is definitely stunted. They should be at least twice that size by now. Even our first spawn when we were complete rookies and had smaller eggs (like yours with smallish parents) they were 3/4"+ by the end of month one. Ours are now about 2 weeks old and the smallest are over 3/4" with the largest nearly 1 1/2" today.

06-06-2007, 12:32 PM
Other than regular water changes any suggestions?
Will they ever grow?

06-06-2007, 02:11 PM
they will but size depends on the parents and environment.

06-06-2007, 10:14 PM
Cindy's right. Parents, both age and genetics, determine growth potential, but you have to give them the feeding and water environment to get the most their genetic potential has to offer. They need plenty of high protein food and good water conditions.
You might want to consider getting some earthworms and making baby food mush out of them:eek1: That might sound gross, but earthworms in a blender make great fry chow when you don't have an ideal fry pond:yes:

06-08-2007, 02:25 PM
I used to raise a tons of fish. Above everything...I found the (2) things that will give you the biggest healthiest fry:
Frequent water changes and live food.

Right now I have about 100 babies in a 20 gallon tank. I also have a 20 gallon with nothing but clean water. Every day I replace water in the fry tank with fresh. Then replenish the fresh tank . It will de-chlore overnight.
This is the single most important thing Ive ever found. Even more than the live food.
I have killie-fish fry that doubled in growth complared to fry in un-changed water over the same 3 weeks.

Also nothing compares to live food. When they are small...live brine shrimp and also grindal worms. You can raise thousands of grindal worms for almost nothing. Look on aquabid and get a culture. In a few weeks...you'll have tons.
More than your babies can eat.
It gives them the best start..then you can move to dry food.


Joey S
06-08-2007, 02:40 PM
cooked egg yolks are high protein, too.

06-11-2007, 04:45 PM
When performing 100% water changes are you netting the fish out and placing them in fresh water or just removing as much water as you can and replacing it?

06-11-2007, 07:54 PM
You can siphon out the old water while adding fresh, do a trickling overflow water exchange, or net them to a temp container while doing a 100% dump and re-fill. I generally just do partial exchanges several times daily.