Rubbery Sealant Used on Reef Tanks
This page is the CodyCross answer for the clue below from Home Sweet Home, Group 635, Puzzle 2 (Extension Cords).
Question is: Rubbery Sealant Used on Reef Tanks
and the answer is: SILICONE
Word Meaning:
SILICONE — (chemistry) Any of a class of inert, semi-inorganic polymeric compounds (polysiloxanes), that have a wide range of thermal stability and extreme water repellence, used in a very wide range of industrial applications, and in prosthetic replacements for body parts.
Definitions from Wiktionary.