The only help I could possibly provide is try an app called inaturalist, it will most likely be able to identify what kind of algae/disease it is. for curing, I haven't a clue. If you find out what it is, you might be able to look up a cure. good luck man.
So I am a beginner, and I have a 22 gallon tank with 4 dalmatian mollies and a gold mystery snail. I have a few questions
1. what do I do if my ammonia spikes?
2. what do I do with unwanted fish? (too much breeding)
3. What do I do to get ph to 7.5 - 8.5?