Repair gap between tile and cover rail?

[xcellent]

Hi All,
My gunite pool is about 2 years old. Do I need to fill-in the gap between the tile and cover rail (if so, what is recommended) or is this something that I shouldn't worry about?

Also, thanks for helping keep the water clear!

 

[AQUA~HOLICS]

Keeping water from entering that area will help prevent erosion and having the soil expand from moisture.
Typically a grout is used in this area, was there an original product installed that has since eroded?

 

[xcellent]

I don't think there was ever anything in it - wish I had taken more pics. Would a builder normally warranty that?

 

[AQUA~HOLICS]

From the picture it does look like nothing was applied to the area.
The builder may have a reason for not filling the void, as stated earlier it being exposed with the potential of water entering the area it may have a negative impact.
If product was in place and has since fallen out I would think it would be under warranty for a reasonable period.