How to Harvest & Protect Your Fish Eggs and Baby Fish
When spring comes around and when the water temperature in the pond reaches a certain level then this becomes a signal for koi and goldfish to start to breed.
At this time behaviour in the pond becomes frantic with the male fish pursuing female fish by literally chasing the female koi or goldfish around the pond.
At some stage soon after this courtship the female lays eggs which attach themselves to structure in the fish pond such as stems of plants.
The trouble with this and especially in a small fish pond these eggs become food
for the larger koi or goldfish and the net result in many cases is that no young
fish develop (called fry). Many of the eggs will develop into tiny fish (fry)
only to be eaten once again by the larger fish.
The natural instinct of these small baby fish is to hide and sometimes the result is a few hatchlings actually survive. These small fish will continue to hide until they become about 1 inch long and suddenly you might notice some small black fish swimming around in the fish pond. These black fish are probably small koi or goldfish. Goldfish in particular will only develop their bright gold colours over a period of time.
The percentage of eggs laid that actually survive is miniscule if left to the natural environment. However you can increase survival rates quite dramatically by separating the eggs and allowing them to develop in a protected environment.
Creating Artificial Structure on Which Fish Lays Eggs
Not every fish pond has plants and therefore any eggs will be wasted if they cannot become attached to some type of soft structure. There are products available such as aquamats and floating spawning brushes (see below) which are placed into pond during the breeding season. In this way the eggs deposited on the aquamats can be easily transferred to an incubator or nursery cage floating in the pond.
How to Protect the Eggs and Fry in A Garden Fish Pond Using Pond Fish Spawning Incubators or Floating Cage and Nursery
A good proportion of the eggs spawned by the goldfish or koi can be successfully reared within the pond by separating the eggs as soon as possible from the parents. This is best achieved by taking parts of plants (or an artificial structure such as an aquamat) on which the eggs have been laid and placing them in some sort of free-floating fine mesh basket . The eggs will then hatch naturally without being eaten. As the eggs become fry the fry are also protected and are allowed to swim freely in the basket. Since these small fish only eat tiny aquatic lifeforms the fine mesh of the basket still allows food to reach the small fish or hatchlings.
Once the fish are big enough to avoid being eaten they can be released from the nursery cage.
Nursery Cages and Floating Pond Incubators
I suppose you can make your own isolation cage but commercial products are available as shown below.
| Spawning Product USA ONLY | Description & Buying Link for Spawning Aid in USA ONLY |
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Pond Fish Spawning Incubator
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Floating Pond Fish Spawning Cage & Nursery
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Aquamats for Spawning Pond Fish
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