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The Goldfish Gazette, Issue #022 -- Goldfish Over Winter
October 30, 2015

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
October 2015
Issue #022

In This Issue
Goldfish Over Winter

What's New On The Website

With the Northern Hemisphere moving into winter, now is the time to consider what needs to be done to ensure your Goldfish will not only survive winter, but be in excellent condition for breeding next spring.

Goldfish Over Winter

Winter is a stressful time for Goldfish that are kept outdoors in a pond.
They may survive the winter, but come spring, many Goldfish die.

Breeding Conditioning/Autumn Feeding

Autumn is an important feeding period for two reasons;

1. Our fish need to be conditioned in preparation for a period of low activity over winter when they will be using up their fat reserves

2. Ensuring they are in excellent condition after winter to enable them to breed in the spring.

Winter Feeding

At temperatures below 50oF (10oC) most Goldfish show little interest in food. The level of interest in food will depend on what temperatures your fish are kept at. My fish do show some interest at those temperatures so I feed them every few days.

Feed your fish food that is high in vegetable matter with little protein. Feed lightly as their digestive system will be operating at a very low level and if you feed as heavily as you normally do, they will leave most of the food uneaten.

Pond vs Indoors

As a general comment, Goldfish can withstand very cold water temperatures for a short time such as over winter. However, not all Goldfish are created equal.

If you live in an area where pond water does freeze, the best varieties to keep outside are single tailed varieties and metallic scaled fantails.

Any other fancy variety should be kept in water that doesn’t freeze, or if you can’t prevent their water from freezing, monitor them closely for buoyancy problems or dropsy.

Another consideration apart from variety is size. Any fancy variety under 2” (52mm) in body length or 3” (75mm) for single tailed varieties should be wintered indoors if the water is going to freeze.

If you do need to winter your fish indoors and want to breed them in the spring, they will need a period of low temperatures around or below 10oC for at least two-three months.

Pond Depth

In the harsher climates where pond water will freeze, it is important that the water depth is deep enough so it won’t freeze completely.
The pond should have a deep spot where the fish will gather and where the water temperature never falls below 32oF (zero oC).

Another problem with water freezing over is oxygen depletion. Even though the oxygen demand from fish will be very low, a solid sheet of ice is going to stop the normal exchange of carbon dioxide out/oxygen in to the water.

Either a hole in the ice needs to be created and regularly checked to make sure it is clear, or a very low wattage water heater specifically made for this purpose needs to be used.

Pond Cleanliness

It is a good idea to have a late autumn clean out of your pond. The reason for this is it gives the opportunity to remove mulm and other debris from the bottom of the pond where your Goldfish will be sitting during winter.

There won't be a problem in winter, but come early spring the debris will start creating ammonia deposits as it starts to rot.

To read more about pond maintenance for winter click here...

What's New On The Website

Costia Disease

I have added another disease page on protozoan parasites, in particular Costia, or more correctly, Ichthyobodo necatrix.

This is a particularly nasty disease if left untreated that can't be seen by the naked eye, so a microscope is needed to confirm diagnosis.

In the past the disease was relatively easy to get rid of using salt at 0.3%, but recently salt resistant strains have started to appear which can resist salt up to 0.9%.

Comments? Ideas? Feedback? I'd love to hear from you. Just reply to this e-zine and tell me what you think, or what topics you want covered.

Next Month's Topic

Aquarium Design

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