When a conduit is placed and activated the game wil slow down very quikly and freezes

So i was in my survival world and i wanted to create a conduit to clear out an ocean monument 

So here is the deal

  -placed the conduit

 -surounded it whit prismarine

 - waited to it to activate for 5MINUTE

then the game freezes but you can see that the conduit is on

No game crash reports and every time i open up the world i get 2 seconds to break a bloc then it freezes again( i suppose this is the time to update the conduit to re-activate when a world is loaded)

This same happends in another world when i create a coduit