Sump - any CUC & how often do you clean?

Thinking about CUC, I'll admit I'm not too excited about them but let's be realistic. Do you keep any clean up crew in the sump?

I also noticed that my roller fleece & even my return pump to some degree are accessible but more like last resort. I don't think I really want to have to clean blindly around them or pull apart unless it's truly needed. Because of that I'd love to keep them clean & be proactive. But also can't even see under around them etc. definitely wouldn't want something crawling out and dying because there's no getting behind it either.

-- Basically, how do you manage the dark corners of your sump?