Since I have added Spawn of Psyduck to a server me and my friends play on, Mew and Rayquaza can spawn in the ocean biome. I have looked it up and someone said to delete all the biomes oplenty sutff, but it still says they can spawn there after I reloaded it.

you need to remove all entries from the BoP config section for everything individually, alternately i should be finished with the update and it should be out this week