[bekko]

I agree with Luke and Maurice. Let the fish do their own thing. If you are going to use hormone injections and strip spawning, then practice a few times on junk fish first so you do not kill your best broodstock. I have never strip-spawned koi, but have done it with some other species. There is a lot of handling involved and it’s hard on the fish. We would tend to lose them 5-10 days after spawning. I suspect this was because the handling stress compromised their immune system and they would succumb to the inevitable bacterial infection.

Put the fry in the mud pond. The first days are the most critical and you want them to have the stable water quality and diverse abundant food of the mud pond. Look up the thread on growing fry in green water which ended about 9-5-2004. There may be others in the archives of this board.

Some like to put the spawning mat in the fry pond and others like to wait and move fry to the pond when they are ready to begin feeding. Personally, I like to put the spawning mats in the pond because the water quality can get pretty rank in a hatching tank from all the hatching debris.

Preparing the pond for stocking is an art in itself. Everyone develops their own technique based on local conditions and what works for them. Here are some steps often used:

• Drain the pond during the winter if you can.
• Dry the bottom if you can.
• Plow the bottom if you can (this works magic and is strongly encouraged).
• If the bottom cannot be completely dried and plowed, then spread some quick lime to oxidize humic organics and kill off some of the bugs.
• Send a soil sample to the local agricultural extension service for a soil analysis. Tell them what you are doing so they will know what to recommend.
• Add agricultural lime at the rate recommended in the soil analysis report.
• Fertilize the pond. Everyone has their preferred method. Some use something like prilled urea which is heavy on the nitrogen. Others use the liquid pond fertilizer while the pond is filling which is heavy on phosphates. Still others use organic fertilizers. I like to add enough of a general balanced agricultural fertilizer to yield about 0.5 to 1.0 ppm of nitrogen when the pond is full and a similar amount of phosphate. Then I also add organic fertilizer at a rate of about 100 to 200 pounds per acre (11 to 22 grams per square meter). The inorganic (chemical) fertilizer gets the phytoplankton (algae, green water) going quickly. The organic fertilizer gives the rotifers, copepods and other zooplankton something for grow on while the algae bloom develops.
• Some like to use the “puddle method” and fill the pond very slowly over several weeks, saying there is better light penetration to get the algae going. I like to fill the pond more quickly to stabilize the temperature.
• Here’s the tricky part. You want to start filling the pond 10 to 30 days before the fry are ready to begin eating. In some areas, you have to stock within 10 days to keep the predacious insects from taking over the pond and eating the fry. In other areas, it takes up to 30 days to get a good “bloom” going. In Georgia, target 15 days and adjust based on the first year’s results.
• Obviously, you cannot predict the exact spawning date so there is some luck involved in getting the timing right. As a rule of thumb, figure your fish will spawn around the time of the full moon after the temperature reaches 68 F (20 C). Cold there this winter, huh? If I had to guess, I would say May 23rd for you, but it might happen at the end of April. February 24th for me (na-ne-na-ne-boo-boo).
• Do not fertilize and fill all the ponds at one time, but stagger them. This increases the odds of having a good pond when the fry are ready to stock. As the time approaches, start monitoring zooplankton. The easy way is to set a flashlight on the edge of the pond at night and wait about 15 minutes. The zooplankton will swarm around the light and give you a quick indication. Alternately, you can pour a liter of water through a small sieve with 30 micron mesh and count the number of food items under a microscope.
• If you can get one rotifer per ml, the fry will love it. Typically, you have to try to get by with less. Ciliates will also work as a first feed but the fry are soon looking for something larger. There is typically a succession pattern. First you will see phytoplankton (green water, single cell algae). Then you will begin seeing ciliates of various types. Then you will start seeing rotifers which are slightly larger. Then you will start seeing copepods which are larger still. I don’t know if its coincidence or nature’s way of taking care of young fish, but larger food items seem to come along just about the time the fish have grown large enough to eat them.
• Some people start providing supplemental feed (out of a bag) immediately. Others wait until the fry have been in the pond several weeks to a month. I just watch the zooplankton numbers and add supplemental feed if the numbers are low. You will want to start with a feed called something like “No. 0 Crumble”, or “fry powder”. Check the feed stores in an area where there are catfish farms or order direct.
• Get some aeration equipment and a dissolved oxygen meter. The combination of spring, fertilizer, green water and feed can depress oxygen in a hurry and young fish are very susceptible. Either run the aeration equipment continuously, or check the oxygen every day at dawn and be prepared to turn it on if the dawn readings start looking low. Tell us the pond size and we can recommend some equipment. Pin Point or YSI brand oxygen meter.

There is a dude named Dr. Gary Burtle at the UG experiment station in Tifton Georgia who can help you at lot. If you can’t get to Tifton, then tell your local agricultural extension agent that you want an Aquaculture Specialist to help you. You will be amazed at what these guys are willing to do for you if you ask them and smile nice.

-steve hopkins