Perplexed - Small (upto 1mm) anchored "jellyfish" like clusters on fixed surfaces

Hi there guys, I was hoping that my first post on this forum would not have to be about a problem I'm having but rather a suggested solution to someone elses'.
As the subject says, I am have discovered a problem with my 55Gal tank which can simply be described as a mass of very small "jelly fish" like objects on all surfaces of the tank. I have searched all over and cannot seem to discover their cause. Does anyone have an idea?
The tank is fully cycled and contains 3 Clown loaches, 1 Pleco and 1 female Betta.
I have only recently had my first successful wrestle with white spot (my baby clown loach didn't make it though) and am worried that this may be a causative affect (the white spot appeared after introducing some new plants).
???
Any support would be great.

I thought something similar (about hydra) except it has bloomed within the last 24 hours. Is this normal for hydra? And is it fatal?
There seems to be a lot out there about Ick and the like but very little about hydra.

They definately are not snail eggs because there are too many. I have attempted to take a photo of it. Please refer to attachment.

I have decided to take a safe route...

The "items" are not attached to, or seem to be bothering any of the tank inhabitants. Since my last use of Malachite Green was 4 days ago (to ensure that the Ick was well and truely gone) I don't think the problem is hydra either.

Hence, I will be removing all the inhabitants from the tank and placing them in my little 10gal quarantine tank for at least 1 weekto ensure that the problem doesn't spead (tank to contain 60% original tank water and 40% new).

With the large tank empty, I will dump it and clean it ... filter and all ... then start a new cycle. I'm not as worried as I was yesterday as there doesn't seem to be a detrimental effect to the inhabitants of the tank - they all ate quite happily this morning.

In the mean time, if anyone does know what it is... please let me know.

I will keep you posted on how they all fare.

Happy in their new Home!!!

As I mentioned, here is a pic showing most of my bottom dwellers, happily exploring their new home. The three loaches are quite obvious but the Pleco (upside down under the top rock) is a master of disguise. When we moved him (in a light coloured insulated box) he changed colour to nearly white! It was a really cool chameleon effect.