Have been using the rhino line type coating now for a while and have had no problems what so ever. They can't scratch through it, see no trouble with the water, no leaks, and easily cleaned.
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2 A. Miss at 8'
5 A. Miss at 3'-5'
1 C. Nil at 9'
1 C. Croc at 6.5'
6 A. Miss/C. Croc 2'-3'
1 Naja kaouthia
1 A. c. contortrix
1 Ophiophagus hannah (but not much longer - gettin old and that snake is fast)