Red Algae introducing Green Algae

I have a problem with red algae in my 30 gallon fish tank. The colony has been in there for an estimated 4.5 years so have not been able to keep an algae eater. Is there any way for me to get rid of the red algae relatively quickly and introduce green algae instead so that my tank can be more healthy for the fish living in it? I have already lost 6 fish to the red algae in the past 2 months.

Bump