Thanks all, really appreciated!
I first expected that they were snail eggs but then seeing those little things flying about I wasn't too sure. Looked up 'Copepod' and the shape seems to fit
We also have some other eggs, which are of a similar size to the first picture but a smaller clutch and translucent blue - guess I'll have to wait and see what comes out of them!
Thanks again, well pleased with responses to my 1st post.