There's a new tag called
wetlab. There seems to be only one (but rather popular) post tagged with this tag. I don't suppose it could generalise to any other question asked so far in Academia.SE.
Is such a tag necessary?
I think the wetlab tag is useful or might become so in the future if this site gets more attention in the natural sciences circles.
Besides, I don't think it's hurting the site in anyways to keep it.
Personally, I do not find that the tag 'wetlab' is necessary. A main point of a tag is to be able to search through questions more easily. I'm not sure that a future searcher would necessarily link that question with 'wetlab' which could more easily be applied to chemistry (for example).