1st pic) the circular ones are hydroid jelly fish. they are neither beneficial or harmful. and the larger thing on the side is somekind of flatworm, which are bad, they eat coral.
2nd pic) looks like flat worms also.
Definetly Hydriods and as stated dont much matter either way.
And do the flatworms look like this, I cant quite tell... If so then you are fine. I had a few and they one day just dissappered, they are benign and eat copepods.