Could be Candy stripe pleco (second photo)or could indeed be a larger clown pleco. Am near certain the third photo is Clown pleco.
Clown Plecos absolutely need wood in the aquarium as it forms a considerable portion of the fishes diet and they are not as proficient at eating algae as the Rubber lip.
The Clown pleco is also not a fish that will be seen a lot as they much prefer to move about after dark.
Kept one for about three years and maybe saw it a half dozen times.