Pink organisms betwin tiles

[grzech]

Hi

I have indoor swiminpool. The the water is chlorinated.
From the beginning, I have a problem with organisms that appear from time to time on the joints (between tiles - I have mozajka)

These organisms are first very small, a size of 2-3 mm and then are able to grow to the size of a thumb nail - 2-3 cm in diameter

Are pink, gelatinous like jellyfish, half-round (taped to the wall) Below a short film how it is attached and how it looks inside - PLEASE CHANGE ON "HD" RESOLUTIUON

https://youtu.be/QUauuiAIAS0

https://youtu.be/mSS1NHcIIEE

if any of you has any idea what it is??, whether it is dangerous and how to fight it

[Denniswiseman]

Your video's aren't working

[grzech]

now it should works

[Denniswiseman]

Hi
That is strange. I haven't seen anything like it before but maybe someone else has and can advise
How is your chlorine level? maybe superchlorinate the pool, brush and vacuum to waste
It doesn't seem to widespread at the moment