A lot of goldfish diseases can be completely prevented if you take the time to pick out healthy stock in the first place. However, that can be a difficult task in itself if you haven’t been keeping Goldies for very long – especially if you’re trying to sort through a tank that has a couple dozen Oranda Goldfish in it. There’s a lot more to check than simply making sure it’s swimming!

How to Choose a Healthy Goldfish

Here’s a quick breakdown of what I look for before I commit to buying any type of Goldfish.

1. Examine the overall appearance of the Goldfish.

Examine the overall appearance of the Goldfish. When I do this I’m looking primarily at the color – is it dull? Does it appear sickly or malnourished? If the color is very pale compared to the rest of the fish the one in question is probably suffering from some kind of stress or illness. You also want to pay very close attention to the belly – a fish with a very sunken appearance to its stomach is likely carrying internal parasites. I also like to take a quick look at the shape of the body – in general, I avoid Goldfish that have a very distorted, deep body because I don’t want to deal with buoyancy problems later on.

2. Observe the way the Goldfish is swimming.

Observe the way the Goldfish is swimming. This should only take you a few minutes – all you are doing is watching the way the Goldfish swims in comparison to the rest of the Goldies in the tank. You should avoid purchasing a Goldfish that is bottom sitting or scratching against objects. Likewise, I don’t recommend purchasing a fish that is already showing signs that is having difficulty maintaining buoyancy. For instance, avoid the ones that have an apparent tilt or occasionally stop to float on one side.

3. Examine the fins on the Goldfish and its tank mates

Examine the fins on the Goldfish and its tank mates. This is a very easy step because there really isn’t a lot that you need to look for. However, the condition of the fins can tell you a lot about the health of a fish. For instance, you do not want to purchase a Goldfish that has any red streaking or white cottony growths along the edges of the fin. If the fins have a very shredded appearance or look like they are being eaten away by something do not purchase anything from that tank!

4. Examine the feces if possible.

Examine the feces if possible. You are ideally looking for a Goldfish that has solid strands of poop, not one that has clear or very stringy poop. However, many Goldfish at the pet store are already suffering from a mild case of constipation because they are only offered flake food, so I would not be terribly concerned with a bubbly or clear strand of poo – instead, I would just fast the fish once I got it home and then offer it organic whole peas for a few days.

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While you are observing the feces, make sure you also take a quick look at the vent (where the poo is coming from). You do not want to purchase a Goldfish that has a bloody or very swollen, irritated vent. The vent area of a Goldie should gently slop upwards toward the tail.

5. Look if it is missing any scales

Look the Goldfish over to see if it is missing any scales. The scales on a Goldfish act like a layer of armor in respect to its immune system – these are the first things that any bacteria or parasite come into contact with. If the barrier is compromised in any way, like a patch of missing scales, the fish is left very vulnerable to infection and disease. Generally, a Goldie that has patches of missing scales will also show other signs of being unhealthy as well. However, occasionally I overlook a missing scale or two because it’s very apparent that they are being picked on by the other fish which isn’t a rare occurrence in an already overcrowded sales tank.

6. Look for irregularities

Look for any growths, lesions or fuzzy patches on all of the Goldfish in the tank. This one is pretty self-explanatory – you do not want to purchase a Goldfish that has any open wounds, ulcer-like markings, or fuzzy patches on its body/fins. You should also be on the lookout for fish that look like they have been sprinkled with salt – if any fish have this appearance do not buy anything from the tank.

7. Observe the other Goldfish in the tank

Observe the other Goldfish in the tank. After you have taken the time to examine the Goldie you want to buy, take a couple minutes to look at all of the other fish in the tank. You ideally want to find a tank that doesn’t have any dead Goldfish floating around.

However, please keep in mind that it will be almost impossible to find a tank that meets that criterion if you are shopping in a large chain pet store. The tanks at these stores are grossly overstocked which makes dead fish an inevitable reality. Instead, make sure that the other Goldfish do not have any visible external parasites, growths or signs of fish ick.

Final Thoughts

The goal of the above check list is to help you pick out a healthy Goldfish; however, it is not implying that you should be rigorously examining the fish to make sure it fits show quality standards. For instance, if the fish you like has a minor flaw, like a bent fin, but otherwise appears healthy then go for it!

The health of the fish is the most important consideration. Just make sure that the new Goldfish will be compatible with your other Goldies.