Marble angels have
random black & grey markings overlaying a silver grey body. They often have
blue flecking in the fins and around the head, and they can have a golden crown.
Homozygous individuals tend to have much more black than heterozygotes. Identification
can be complicated by the existence of another marble gene - gold
marble which is an allele of marble. To further complicate the issue interaction
with other genes can also affect how the marble gene expresses.
Please note that the fish above is M/M Z/Z that is to say it has two marble genes & that it also carries two zebra genes.