Reef 
To dream of a reef suggests you are repressing your emotions. You are preventing unconscious thoughts from manifesting in your life.
Knots
To dream of knots represents your anxiety over trivial things. You may be seeking for a solution to a problem at hand. It also suggests barriers and restrictions in your thoughts and emotions.
To tie a knot in your dream symbolizes self-sufficiency and an unyielding nature. You enjoy being in full control of situations. To dream of a knot may also symbolize a coming together of two persons, such as an agreement or a commitment to a relationship as commonly referred to in the phrase 'tying the knot.'
Coral
To dream of coral represents the magnificence of the natural world around us. In order to achieve true bliss and eternal pleasure, you need to recognize and understand your inner emotions. It may also signify decency, integrity, and the essence of life.
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