"Dxbuae" wrote...


Koi fish breeding, need help?
I want to ask about koi fish breeding.
I always face the same problem when I do breed my koi fishes.

I use the method of isolating a female fish with a male in a separate
tank. The process of spawning happens normally and the female lays her
egg. But the problem is that I am not sure if the male had thrown his
sperms over the eggs. I can see the eggs in my spawning ropes, but not
sure if the male released his sperms. My question is: can the female koi
release her eggs and those eggs are not fertilized by the male koi
sperm?

I close the filter and use only oxygen in the tank.

I usually wait for 5 days but nothing appears from those eggs. In fact,
there is an awful smell coming from the tank and there are some white
substance floating on the water tank. Please need your advice? How can I
complete the breeding process?
.................................

Never deliberately spawned Koi but have, in my youth, spawned a number of
tropical fish. I've also kept Koi for longer than I care to remember, the
days when you could buy a 6 inch Japanese bred Tancho Sanke for under £5.
and proper dark Showa were common, not these modern mostly white things.

Firstly it's usual to ensure fertilisation of the eggs by having two males
to each female in the spawning pond.
With only one male it is more than likely that some eggs won't be
fertilised. These will turn white and become infected which is not good for
the remaining healthy eggs so white eggs should be removed quickly.

Fertilised eggs are sticky and stick well to anything they touch so turning
off filtration at this time is the opposite of what is needed, eggs need the
cleanest water possible and a flow of oxygenated water over them. I trust
you also remove the parents asap or they will eat the eggs and pollute the
water.

Once the fry hatch they will not need food for a few days while they live
off their egg sack so don't be tempted to feed them immediately and pollute
the water. I used to use Brine Shrimp for the tropicals but daphnia work for
most fresh water fish, what do you usually have ready as a first feed?

--
Regards
Bob Hobden
W.of London. UK