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The Goldfish Gazette, Issue #019 -- Goldfish Compatibility
July 30, 2015

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
July 2015
Issue #019

In This Issue
Goldfish Compatibility

Goldfish compatibility is just as important between Goldfish varieties as it is between other species.
The physical characteristics of some goldfish are so extreme, they should be considered a different species.

Goldfish Compatibility With Each Other and Other Species

This month I want to re-emphasize the importance of considering the physical characteristics of different Goldfish varieties before deciding to keep them in the same environment.

Goldfish are non-territorial and non-aggressive towards their own kind, usually swimming around in loose groups. However, when it's feeding time, it's every fish for themselves.

And this is the biggest issue with mixing varieties.

Mixing Common Varieties With Fancy

Imagine an aquarium full of Comet Goldfish, and one Black Moor. This or something similar isn't an uncommon scenario. The Comets seem to be healthy and well fed, but the Black Moor seems underweight and lethargic.

That's because it is starving to death.

The rules to be applied when mixing varieties are:
1. Single tailed varieties together

2. Twin tailed varieties together and

3. Normal eyed varieties together.

So applying these rules, Common, Comets and Shubunkins can be kept together, Moors, Water Bubble Eyes and Celestials can be kept together, and all other twin tailed varieties can be kept together.

This is a good starting point but there are exceptions.

Physical Development With Age

Fantails and Veiltails both have twin tails, and when they are young, both varieties can be kept together successfully.

As goldfish age, their characteristics become more developed. A Fantail's fins won't develop much more from the size they are after the first few months of life. However a Veiltail's finnage will keep growing for some years.

This means the veiltail will progressively become slower and slower with age, and be less able to keep up with the fantails.

Another example are Lionheads. They can take five years to fully develop their hoods, when their eyes can become completely covered. At that stage of development, they can't be kept with normal eyed fish.

Goldfish Compatibility With Other Species

Ideally, each Goldfish variety should be kept together and Goldfish kept with Goldfish, but some aquarists like to mix things up a little.

I recently visited a fish forum and one of the posts is copied below word for word.

"I recently bought an aquarium which is about 2ft in width and 3.7-3.9ft length. I have 6 gold fish, 2 tiger shark, 2 Yellow Gold Fish Carrasius auratus, 2 white fish, 2 black moor, 2 Ranchu Goldfish, 2 yellow fish with black wings and tail, 2 kissing gouramis, 2 suckers."

This person was having issues. I am not surprised!

Ignoring all the Goldfish rules that have been broken, the person seemed to have little idea of what fish species they had. One can safely assume they also didn't do any research into their behaviors or requirements either.

The first rule when considering other species is, only mix them with single tailed Goldfish varieties, especially in a pond.

Size Differences

Goldfish will eat any fish they can get into their mouths, so suitable aquarium inhabitants such as White Cloud Mountain Minnows or Zebra Danios should only be kept with small goldfish.

For ponds, Koi are an obvious option. Although peaceful, they grow far larger than Goldfish.

Other species suitable for ponds are Golden Rudd and Golden Tench. Golden Orfe need a larger pond and will attack smaller goldfish.

Window or Dojo Loaches are a good option, but they don't like any salt in their water.

If you have a Bristle Nosed catfish for algae control, these can become aggressive as they get older. They will attack Goldfish to try and suck the slime off their bodies.

So the key points are:

  • Don't mix Goldfish Varieties that can't compete for food equally
  • Generally only mix single tailed Goldfish with other species, especially in ponds
  • Carefully watch for aggressive behavior and fin nipping which is common with tropical fish.

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

Goldfish Feeding

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