Lag in the sea/ocean biome

I'm playing minecraft bedrock 1.4.4 and it's not lag, but after i updated to 1.5.0.14 it's so laggy when i go to the sea...i asked to my friend, he said it's because of the aquatic update. but, i when im playing minecraft bedrock 1.6 beta it's not lag just like playing 1.4.4 version...please help me

My device : LG Q6