I have this world that I created back in 1.8 and it adjusted fine with each update up until 1.14.

When 1.13 was released I filled those old empty oceans with the update's seaweed and coral and all that stuff, it worked fine until 1.14. Now whenever I go close to the oceans the game craps itself and lags as if I had high ping on a server, chunks start loading slowly, extreme rubberbanding, particles and placing blocks delayed but this is a singleplayer world. The lag stops whenever the ocean is out of range, but this is annoying due to the fact most of my builds are near said ocean. I've tried using the 'optimize world' feature but that didn't help.

any version after 1.14 has this problem.