black spots on gfish

Question
My goldfish has been getting these black spots that are now coming more rapidly and has now effected another goldfish.

Answer
Eliza,

Sorry to hear your fish is sick. Usually black dots are ammonia burns, but it could just be his coloring coming though. Check your water to make sure the ammonia hasn't spiked up. I don't know what size your tank is. So, how big is your tank and how many fish do you have in it? To help this from happening again, make sure you do water changes every week, especially if the tank doesn't have a filter. The black dots are the ammonia burn in its healing process.

To help this i would do a large water change, 50%, then for about 5 more days do a smaller change like 20%. This should clear it up, if it is ammonia burn. If it doesn't, just let me know.

Hope this helps.