I doubt that the bucket is the physical body in the analogy used. The bucket is the ego and the water in the bucket is most probably the mind.
MASTER (to M. and the others): "Is it an easy thing to obtain the
Knowledge of Brahman? It is not possible unless the mind is
annihilated. The guru said to the disciple, 'Give me your mind and I
shall give you Knowledge.' In this state one enjoys only spiritual
talk and the company of devotees.
(To Ram) "You are a physician. You know that medicine works only when
it mixes with the patient's blood and becomes one with it. Likewise,
in the state of Brahmajnana one sees God both within and without. One
sees that it is God Himself who has become the body, mind, life, and
soul."
M. (to himself): "Assimilation!"
MASTER: "A man attains Brahmajnana as soon as his mind is annihilated.
With the annihilation of the mind dies the ego, which says 'I', 'I'.
One also attains the Knowledge of Brahman by following the path of
devotion. One also attains It by following the path of knowledge, that
is to say, discrimination. The jnanis discriminate, saying, 'Neti,
neti', that is, 'All this is illusory, like a dream.' They analyse the
world through the process of 'Not this, not this'; it is maya. When
the world vanishes, only the jivas, that is to say, so many egos,
remain.
"Each ego may be likened to a pot. Suppose there are ten pots filled
with water, and the sun is reflected in them. How many suns do you
see?"
A DEVOTEE: "Ten reflections. Besides, there certainly exists the real
sun."
MASTER: "Suppose you break one pot. How many suns do you see now?"
DEVOTEE: "Nine reflected suns. But there certainly exists the real
Sun."
MASTER : "All right. Suppose you break nine pots. How many suns do you
see now?"
DEVOTEE: "One reflected sun. But there certainly exists the real sun."
MASTER (to Girish): "What remains when the last pot is broken?"
GIRISH: "That real sun, sir."
MASTER: "No. What remains cannot be described. What is remains. How
will you know there is a real sun unless there is a reflected sun? 'I-
consciousness' is destroyed in samadhi. A man climbing down from
samadhi to the lower plane cannot describe what he has seen there."
The Gospel of Sri Ramakrishna, At the houses of Balaram and Girish, May 9, 1885
There is no causal body in the analogy. Ego and Vasanas are parts of the subtle body.