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Northern Winter care of the pond

Care is different for Lily ponds versus goldfish ponds versus koi ponds. We present here a generalized look at winter care, please keep in mind your special situation in regards to your fish load and your climate, I'm sitting in Buffalo, NY so my low temperature and ice thickness is lighter than those of you in Minnesota for example.

1. Fish inside or out? small goldfish can be easily over-wintered in most ponds, even 18" preformed pools. Larger goldfish and small koi desire a spot 30" deep. Larger Koi 12" and up need 30" - 48" depth to be safe. This doesn't mean the whole pond, just a spot. In our fish pond installations we usually create a deep spot that is 30% of the pond.

2. Leaves -Consider a leaf cover, it is ESSENTIAL to get leaves out if you are over-wintering fish. Clean up marginal plants as soon as frost knocks them down, the spent foliage must not be allowed to fall into the pond and pollute. You do not want rotting leaves and fish waste to pollute the pond as the fish will NOT survive. We strongly recommend after physically removing the leaves and debris to add beneficial enzymes that will consume the inevitable sludge you miss as it gets colder. We use Spring and Fall Prep and Muckoff tablets. Water quality in late fall should be great, your water should be crystal clear, if not do small water changes. (Make sure you don't change the temperature of the water more than 2 degrees, as this will cause fish stress) It is imperative to keep the bottom as clean as possible, this why experienced fish keepers never put stones in the bottom. The specific problem is growth of psuedonomas and aeronomas bacteria. The symptoms of these two "bad" bacteria's do not show up until late spring. As temperature of the water increases they attack the fish. Many of our clients have been happy with over-wintering their fish and then loose them in April and May never thinking it was winter sludge activity that killed them. Your fish should be never happier than they are in late fall, as water temperature drops it holds more oxygen and their metabolism slows down.

3.Hardy Plants - hardy plants can be allowed to dieback on their own or cut back, except the ones in small tubs and container gardens. Cut plants to 6" from the top of the pot and place in bottom of pond after the first heavy frost. However, hollow stemmed plants should be trimmed above the water line. Trimming these below the water line could cause rotting. Drop hardy lilies down to the deep part of the pond 30". If you do not have that depth store them in their pot mud and all in a frost free location. Hardy marginals like Iris can be dug in (pot and all) somewhere in your gardens. Cut back water lilies to about 1 inch above the soil, replace soil and gravel as necessary. Keep hardy oxygenator plants uncut in the bottom to reduce early algae problems in spring. Oxygenating Plants: Cut back to 2 to 3" above pot and place in the bottom of the pond. Decaying plants will foul water quality and should be removed from the pond.

4. Annual plants -

All floating plants including water hyacinth and water lettuce should be discarded unless you bring them indoors and keep the water temperature at least 70 degrees F. and use a good grow light.....a rather expensive endeavor. Tropical lilies should come inside when water temperature goes below 70. Why many people consider these annuals and toss them, I have always had good luck by washing off the soil, wrapping them in damp newspaper and put in tray of perlite or peatmoss , then storing them in a cool dark spot.

5. Critters- Remove all tadpoles, snails, and frogs, Snails and tadpoles have a hard time overwintering, so bring them in. Release the frogs into your yard. I PROMISE they will find your pond again next year. Keep checking weekly for fogs because if they stay in the water they will die. Their corpses are toxic to fish and the smell in spring is something you don't need to experience.

6. Ice - with fish overwintering it is IMPERATIVE we have some open water for gas exchange. This is the most important winter task!

Pond Deicers are available from the 100 watt to 1500w units that will keep a hole in the ice and are controlled by a thermostat. We are NOT heating the pond. For best results combine with a aerator to avoid issues with snow load etc on pond. Position deicer directly above aeration bubbles for best results. The year around benefits of aeration are enormous. We stock heavy duty air pumps, these units use as little as 4 watts of power. Remember, if the pond freezes over, the freezing is not what is killing the fish, but trapped gases asphyxiate them. You must keep a hole open even if you have to melt a hole with a hot pan.

(Old Wives tale #23 - "breaking the ice with a hammer will send a shock wave and kill the fish - FALSE!)

7. Fall Fish Feeding- feeding when water temperature is below 50 will kill your fish, they don't have stomachs and cannot digest food in cold water. Suggested feeding schedule:

70 + twice a day or more with a fresh high protein food like Sakana Fish Food that we use ourselves.

61+ twice daily

56-60 Feed just once a day.

51-55 feed 2 to 3 times a WEEK

42 -50 Spring/Fall Wheat Germ blend foods only

< 42 no feeding

don't watch the calendar- watch the thermometer on when to feed.

8. Salt- if you remove your plants you should salt the pond to a rate of 3 lbs. per 100 gallons. Pond salt kills 7 of the 10 common parasites. The salt level will be diminished in spring by your first water changes before the plants go back in. Most people find bringing fish through the winter a easy task, but then they tell us they died in spring. two words: BACTERIAL INFECTION. The salt prevents a lot of this, plus it improves gill function and helps the fish create more of it's natural slime coat. Pond Salt has no iodine or YPS anti-caking agents that kill fish and found in most commercial salt sources.

9.MOVING FISH INSIDE: when you move fish to their inside tank, do so gradually. Move a few in at a time to a tank that was set up in advance with pond water. Make sure their winter home is large enough. Bring as many plants in as you can, even run grow lamps on 10 hour timer. If you don't put plants in be sure to cover with netting. As you add each new batch of fish monitor pH, ammonia, and nitrite, If you are not sure your getting enough aeration, check with a oxygen test kit. Feed very sparingly the first week to avoid a ammonia spike. Consider ammo rocks etc, if you have to bring all the fish in at once. After your filter system shows it can handle more feedings, you'll be amazed at how much they grow this winter.

10. Equipment - Job #1 -remove check valves so pipes can flow! Remove any piece of water holding equipment that is closed including UV Sterilizers, Pressure Filters, Bead Filters. Open top equipment like Filterfalls and skimmers are fine. Take the pump out and store in a pail of water. While you have it out, clean and inspect. Magnetic Pumps should have the magnets pulled out and chambers cleaned. Oil bath pumps should have the oil inspected if it is not clear the seals need to be replaced.

Not sure of your pump condition? - bring it to us, we are available all winter.

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