The tempeature in Kelven is what influences the color spectrum. Warmer (redder) is lower ie 3000K, Natural sunlight is 5500K and cooler (bluer) is a higher temperature rating like 10000K and above. The led fixture you have is most likely around 6700k with blue bulbs to give the appeariance of a higher K rating. Blue light will ten to wash out some of the red color. So you would idealy want somthing with a warmer color to get the red to pop. With the T5 double fixtures I would use a combination of 6500 & 10000K even though the 10000K bulb gives a blue/white light it does have a strong spike in the red so this combo worked best for me.
As far as the algea goes cut down on the amount of time the light is on. How deep is the tank and what are the specs on the fixture in lumins? The light might be too much for the tank. IDK what you have but cutting back on the duration will help.