What's the black spots on my goldfish?

fish is slow & laying on bottom of tank.
small flat black spots on top of head

black spot/black smudge?

we have no snails in the tank

please give help. for each piece of advice I will answer 2 of your questions.

thanks.

Hi,

Most commonly, black spots on goldfish are actually burn wounds from ammonia spikes. Over-crowding, poor water conditions and over-feeding can lead to ammonia burns and persistent ammonia spikes are lethal to the fish. There is also a 'black-spot disease' caused by snails. This is more common in ponds but if you purchase your goldie from a fish store where snail infestations are prominent, this could be the source of your problem. A salt dip is recommended and frequent water changes necessary. There is no over-the-counter medication for this disease.