I'm using a pair of 24" Sat+ lights on my 17g rimless at the moment. Getting about medium/high light from it. A single light on your tank would get you in the range of the upper part of low light.
Overall, I love these lights! The customizable color output, presets, and dynamic modes just make these LEDs fun to own. I enjoy having the flexibility of dimming the lights at night or earlier in the day before I have them on full blast for photosynthesis. I also added the new Current Ramp Timer to one of the lights to have a programmed gradual sunrise and sunset 1 hour before and 1 hour after the 2nd light turns on.