Minimum node separation in fdp graphs

Hi. In my fdp graphs the nodes are sometimes so close together that there’s no line, only the arrow. How do I get them spaced apart better? I tried adding -GK=500 and -Gnodesep=500 without effect.

I am not an fdp expert, but some guesses:

Thanks. The only thing that had any effect was sep. I got what I wanted with -Gsep=+10,10

It might be useful to explore the “overlap” value described in overlap | Graphviz as it states that fdp can run the same overlap removal phase as the other tools.