I think these two pics are of the same red seaweed
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...are notoriously difficult. You need close ups of them out of water to see edges, holdfast pics, and very often even this is not enough you need microscope ID. I think you'll be lucky to get an ID from these pics :)
I think this is right. Pretty distinctive red, slimy linguine. Much branched with flattened hollow stems. Now, I can't see all of that but I have some in front of me as I write - what better! See http://www.ispotnature.org/node/652418
Some very recent help from JoC - I hope she comes here..
Lat/Lng: 51.5668, -3.98
OS grid ref: SS628871