First thing I consider worth knowing is that there are basically two types of "algae," one being the common green that occurs on all surfaces in the biofilm and which we often do not even see, and includes diatoms. The other type is what I term "problem algae." Two quite different things, and different methods are needed to resolve the latter.
Problem algae is not likely to be eaten by any fish. Snails may (but slowly), shrimp sometimes. But any fish that might eat problem algae is usually not suited to most home aquariums.
The other thing is live plants. In planted tanks, it is crucial to keep problem algae under control. It can smother plant leaves, killing the plant in time. It is not particularly harmful to fish, though the situation may be due to deteriorating water quality and this obviously will be in time. In a tank without live plants, you are best to let it be. It is doing what all plants do, using nutrients in the presence of light, and oxygen is produced as a result. Not harmful in itself.
Assuming this is a planted tank, you need to establish or re-establish the light/nutrient balance. Which brings me to your new light...what you have seen is common when light is changed. I have noticed just changing the tube will affect things, usually increased plant growth which obviously starves problem algae more. I have seen algae begin to increase when I neglect to change the tube within 12 months. Sometimes the balance can be pernikity.
If you do have plants, I can take a look at what might be out if you provide some data. Light type, spectrum, duration; any plant fertilizers/additives. Also a photo of the tank so I can see the plants will help.