Lymphocystis is a virus (herpes). It is mostly seen in goldfish, but
getting more common in koi. It was thought that it invaded through external
damage, but now it has been found to be a spore taken in through gills or
These tumors are of many shapes, and koi forms differ from
goldfish and seem larger on shubunkins. Why this is so I do not know.
have seen this problem in the best well run koi ponds, as it has nothing to do
with water condition or fish health.
The remedy sold for treatment
(generic acriflavin) is a complete waste of time.
Lymphocystis is a
giant single cell tumour which may produce one tumour on a fish or a dozen - I
am afraid its down to luck.
I have seen fish cost £6.00 to
£22,000 with this problem in good water and others in ponds you wouldn't
put your mother-in-law in (well some may)!
I do have a treatment for
this problem, but will leave the fish scared and takes up to six months to
What to look for is best described as a small cauliflower, which
gets larger - I've seen one as big as a hens egg.
In the early stages it
is the same colour as the fish's skin, but with time turns red or purple as
seen in photo.
Lymphocystis around the mouth is quite uncommon - see
There is far more to this problem that I can describe in
these few words. For more info contact
This treatment is not the same but very
similar to product no1, to which you add alcohol.