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The Goldfish Gazette, Issue #104 Common Flaws in Pet Shop Fish
August 31, 2022

Goldfish Care Tips

A Free Monthly Resource For Goldfish Enthusiasts
August 2022
Issue #104

In This Issue
Common Flaws in Pet Shop Fish

Most Goldfish purchased are from a pet shop or specialist local fish store, but a growing number are being purchased online, often sight unseen.

Common Flaws in Pet Shop Fish

Comet with rounded caudal fin tips, not pointed

From whatever source you buy your Goldfish, the quality can vary greatly. We can’t expect high-quality fish when we are paying a few dollars for them, but we should expect the fish to be a reasonable representation of their variety.

Generally, larger fish command higher prices because a breeder/supplier isn’t going to bother raising low-quality fish that may not attract customers as it takes the same amount of time, effort, and expense to raise low-quality fish as it does high-quality fish.

The vast majority of larger fish I see for sale on the Internet are high quality. The prices, of course, reflect that.

Common Flaws

If you don’t intend to breed your Goldfish, then the main criteria for selecting a fish to purchase is whether you like the look of it or not, but some flaws can affect how well it will thrive in an aquarium with other fish. Before listing common flaws in a few popular varieties, there are a few flaws that can be present across any variety.
Deformed Mouth - These fish are usually smaller than their tank mates because their deformed mouths restrict how fast they can eat.
Bent or Twisted Caudal Fin(s) - This is more of a problem with twin-tailed varieties. Both caudal fins should be the same size and shape. If a single-tailed variety has a twisted caudal fin it is usually due to injury.
Swimming Motion/balance - This flaw occurs in deep-bodied varieties, and the deeper the body, the more common the flaw. This flaw is most obvious when the fish stops swimming, because the head drops and points downwards.
In some varieties such as Pearl Scales with golf ball shaped bodies, it is a very common flaw.
Age/stunting - This isn’t a flaw, but something to watch for. A fancy Goldfish can be 25mm in body length at 8 weeks old, or at 8 months old if it has been kept in a poor environment. Look for adult characteristics such as breeding stars in smaller fish, which indicates they are probably 12 months or older.

Common Flaws of Popular Varieties

If you are intending to breed your Goldfish, and want to improve your stock, you need to be a little more critical of the fish you are planning to purchase, and the more developed the variety, the more flaws it can have. Comets – Fins are either too short or rounded at the ends, especially the caudal fin.
Fantail/Ryukin and all deep-bodied varieties – Bodies too long, caudal fins have no division or only a single tail present (except for Tamasaba which are meant to have a single tail).
Orandas - Fantails are often sold as Orandas (at a higher price), but no wen develops.
Moors – Eyes not large enough or are uneven sizes.
Water Bubble Eyes – Water sacs are too small (toad head), or are uneven in size. No dorsal or part dorsal fin should be present.
Celestials – Eyes have uneven development, or not turned up enough. No dorsal or part dorsal fin should be present.

I have, and will continue to purchase fish with major flaws if there is nothing else available. It just takes a few more breeding cycles to remove the flaw than if I had started with high-quality fish.

For detailed information on what standards apply to the more common varieties, click here…

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 to be covered.

Next Month's Topic

Aeration and Water Currents

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