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The Goldfish Gazette, Issue #106 Feeding Competition
October 29, 2022

Goldfish Care Tips

A Free Monthly Resource For Goldfish Enthusiasts
October 2022
Issue #106

In This Issue
Feeding Competition

Unequal feeding competition usually occurs when unsuitable Goldfish varieties are mixed in the same aquarium or pond, but excessive feeding competition can also occur within small groups of fish of the same variety if too little food is fed.

Feeding Competition

Severely under-fed Goldfish

Feeding is one of the basic care requirements to get right when keeping Goldfish but so often we see examples of fish that are under-fed, either because their owner isn’t feeding enough, or they have too much feeding competition between tank mates.

How Much To Feed?

The most common answers to the question on the Internet are:
1. What the fish can eat in two minutes or
2. Feed an amount the size of the fish’s eye.

These amounts are fine if you are feeding your fish multiple times throughout the day, but are far from adequate if feeding once a day.

These guides also make no allowances for the season, fish age, or how Goldfish eat, having only a rudimentary stomach.

Excluding feeding to condition fish for breeding, or when temperatures are below 10oC (50oF), Goldfish should be fed between 0.5 and 2% of their body weight daily. 1% is a good average for adult fish, young fish under 12 months old should be fed closer to 2%.

It is fine to be feeding the correct amount but does that ensure every tank member is receiving their fair share?

Signs of Excessive Feeding Competition

Size differences – smaller fish not growing at the same rate as the other fish, if at all.
This is quite common with a mixed variety aquarium and the most developed fancy such as a Black Moor is undersized compared with its tank mates. Ultimately, through malnutrition the fish gets sick and dies, reinforcing the myth that fancy varieties are weak and don’t live long.

It can also occur with just two fish of the same variety. If the owner is feeding too little for two fish, one of the fish is going to become dominant and get most of the food.

Hyperactive fish - this fish is usually the fancy variety that is unable to compete for food with the other tank mates, for example, a Water Bubble Eye competing with Ryukins.

Some pet shops feed a starvation diet to their fish because this causes them to become more active making them appear healthy and therefore more saleable.

Thin fish - To become thin, a fish has to lose a lot of body weight, yet some owners fail to see their fish getting thinner and thinner, probably because it occurs gradually over some time.

Buoyancy problems - more common with fancy varieties trying to compete with less developed varieties, but I have seen the problem occur even with single-tailed varieties.

The fish is assumed to have a swim bladder problem, but the real problem is the fish is undernourished which has caused the swim bladder failure.


Firstly, make sure you are feeding enough food daily to your fish, taking into consideration the season and age of your fish, and secondly make sure you don’t have too much feeding competition in your aquarium.

To read more about feeding Goldfish, 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

Aquarium Cycling Myths

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