I read on a another forum that this could be a result of the colors I used.
Yes, specific color combinations will make monitor ghosting more noticeable. Sharp contrast differences will often do that (e.g. red/cyan, red/black, white/black, …).
If ghosting bothers you, try using more muted colors with lower contrast between the foreground and background during testing.
You can also play with your monitor's overdrive settings, but increasing overdrive too much will cause reverse ghosting to appear as the monitor will overshoot when attempting to correct the initial ghosting.
