Clear sacks on glass (??)

These are racking my brain. I've been searching all day and the best I can think up is sponge larvae maybe? They are attached firmly at one end to the glass and are about a millimeter in size. They're rubbery and if I try to rub them off I can squeeze the nucleus out (someone just warned me about squishing things in a reef tank). They look like eggs but as far as we know there are only Astrea and Nassarius snails in the tank and their clutches don't match, I've been searching in the dark but see nothing else but little fan worms and pods. The pics aren't that great but you can see how scattered the clusters are, close to the surface and powerhead flow. I have pretty good eyes so I was able to get about five inches from them and still focus. From what I can see, I was able to make the last pic up. I know someone here has to have seen these before or can head me in a better direction with my searching. This tank has been running with LR for two weeks. Thanks for any help in advance.

(these are stuck on the front glass, not the powerhead)

 

I think they are little scypha sponges thanks to a tip from a reef forum member.

 

I can't say anything about pics 1 or 2. However, pic 3 isn't a scypha sponge.

To be honest, I don't have a clue what it is. Looks like a pregnant flatworm.

 

I feel like an idiot. When I was searching snail eggs I used the term 'nassarius vibex eggs' and found images of tightly formed clusters that resemble fingerprints. Today, after reading some material that got me back on the track of thinking these are eggs, I searched 'nassarius eggs' and low and behold, I find plenty of images of what I have clearly being laid by nassarius.