Question: Some claim that some deceased relatives, whose ashes have been scattered in the sea appeared in their dreams to complain that they are very cold. How should we see this ‘phenomenon’? Does this mean sea burial is not a good practice? If it is alright, how should we ready others for it?
Answer: If these dreams were truly given by the deceased, this should be because they lacked proper guidance (开示) and support-chanting (助念) to be reborn in Pure Land (净土), to be free from rebirth. They were thus habitually attached to their remains. This should be practised to guide them: https://purelanders.com/wake.
If these dreams were not truly given by the deceased, this should be because the dreamers have survivor guilt, thus subconsciously creating these dreams. Such dreams will usually be brief and vague. If uncertain whether the dreams were self-induced, the practice in the link above should still be done for peace of mind.
Sea burial is alright for those with ample proper guidance and support-chanting offered, ideally with auspicious signs (瑞相) of having reached Pure Land too. Those open to sea burial when alive are not likely to be attached to their remains too, perhaps exactly because they were already focused on reaching Pure Land.
The best place to settle the consciousness is not in some big grave or fancy columbarium. If the deceased settle in either, or even the sea, this means they have or might become wandering spirits, which is unfortunate, as such aimless haunting will still end, forcing karmic rebirth sooner or later, for better or worse.
Question: What if the remains of the deceased have many bones. Can they still be scattered? What if there is some hesitation by family members, on whether to scatter the remains in the sea or to store them? Are there ways to ‘appease’ both the living and deceased reasonably?
Answer: You can ask the crematorium to grind the bones finer for easier scattering. (This should come with no extra charge.) Ash-scattering does not have to be ‘all or nothing.’ It is alright for the living who are attached to encase a few small fragments, such as those with relics (舍利), to place them on their home Buddhist shrine.