If Epotec is applied over a surface which has different areas of porosity, such as Render or Marblesheen, the first coat may soak in more in some areas than others. The result the next morning is you see areas that are glossy and areas where it’s “flat”. (See the first picture). The second coat however will even all this out and your pool will have a uniform glossy finish, as seen in the second picture.

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