Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Bubble eyed goldfish

bubble eyed goldfish
Bubble eyed goldfish


The bubble eyed goldfish is called suihogan in Japan. It was developed in China around 1908 or possibly a little earlier.

Special features

  • Twin tailed.
  • No dorsal fin.
  • Large fluid filled sacs under each eye.

The tails should be forked and completely split from each other. The back should be evenly curved with no sign of a dorsal fin, poorly bred fish will often have kinks or some unevenness where the dorsal fin should be. The sacs under the eyes should be well developed and even in size and shape.


Temp - 65 to 70°F.
Ammonia/Nitrite - no trace.
Nitrate - < 20ppm.
pH - 7.5
GH - avoid extremes.
KH - 5 to 12.

Bubble eyed goldfish are quite delicate creatures. It is slow moving and very easily damaged by anything sharp or poor handling. Bubble eyed goldfish are unable to compete with more ordinary fish, they are easily bullied and easily damaged because of this they will need a tank of their own.

Use fine sand or a bare bottomed tank because gravel could damage their eye sacs. It is also very important that there are no sharp edges on any aquarium decor included in their tank. If a power filter is in use make certain that it is fitted with a strainer over the intake pipe, take every care when siphoning water out of the tank during a routine water change because it only needs one second for a lapse of concentration to end up with a very distressing eye injury to one of these fish.

If one of the eye sacs is ruptured make sure that the aquarium is kept clean and use a general anti bacterial treatment until healing starts in order to prevent any secondary infections. The sac will heal and refill but it may never reach its full size and there will be an imbalance between the eyes which won't affect the fish's health but it would ruin a show fish. Bubble eyed goldfish don't have the extreme body shape common in a lot of fancy goldfish and as a result they rarely suffer from the floatation or sinking problems often associated with fancy goldfish in general.

Goldfish are omnivores with a slight preference for vegetable matter. The main thing when it comes to feeding them is to ensure they have a balanced diet for healthy growth and resistance to disease. Their mouths are slightly down-turned and it isn't natural for them to feed at the surface and it can lead to swim bladder and other digestive problems if they are forced to, so ideally all dried food should be pre soaked prior to feeding so that it will sink. Suitable food

  • Pellets preferably sinking ones Algae wafers
  • Pre soaked flake food.
  • Lettuce, cooked Peas without their skin, Brown Bread
  • Live or frozen Bloodworms, Adult Brine Shrimp, Daphnia.
  • Freeze dried Tubifex.

If you go away on holiday rather than risk someone with no experience feeding them it is better if the fish are left without food.

For a healthy Goldfish to go two weeks with no food will do no harm at all. Being cold blooded their food requirements are far less than an equivalent sized mammal but the risk of over feeding poses a very real threat to their lives.

Ethical note

It has to be said that the bubble eyed goldfish is one of the more extreme varieties with the lack of a dorsal fin and the large fluid filled sac under each eye. This does mean that if the fish is not given the right care and environment there is a very real chance that it will come to harm and have a miserable existence.


  1. Depth of body to be greater than 1/2 of body length
  2. Eyes to have a sac under and around the sides of each eye
  3. Dorsal fin to be absent All other fins to be paired
  4. Caudal fin to be divided and forked
  5. Extremities of fins to have a rounded appearance
  6. Minimum length of body to be 5.5 cm (2¼ inches)

Other areas of judging include:

  • Fish will be bright, alert and well balanced.
  • Body to be short, not elongated, with smooth contours and showing no signs of a dorsal fin
  • Caudal fin to be well divided
  • Eye sacs to be well developed and evenly matched


  • Metallic - Self – red, orange, yellow, blue, brown, black.
  • Variegated- red, orange, yellow, blue, brown, black and silver - any combination of the listed colours in a pleasing pattern and similar on both sides.
  • Colours to appear as burnished metal, extending into the fins.
  • Calico group - blue background with patches of violet, red, orange, yellow and brown spotted with black

Points system

  • Body 20
  • Colour 20
  • Finnage 20
  • Special characteristics 20
  • Condition and deportment 20
  • Total 100

Red bubble eyed goldfish

Note about the photos, the article states that gravel is unadvisable with these fish yet the photos show them in tanks with gravel.

Well, I take almost all of my own photos for this site and I have to get the photos where ever I can. These fish were photographed in a shop (with permission) so I had no control over their care.


Bristol Aquarist Society


North East Goldfish Society