Yo bro,
If I remember,
More flow results in less dead spot in your tank. If you notice, areas with low flow will tend to have more diatom, hair algae etc. Furthermore, uneaten food will stuck at some corner with low flow, and rot....
A high flow will also results in a higher turnover of your water to your sump, thus , ya be skimming more efficient.
Pardon my expression error.
Ps: my cheato still growing...