Flagstone grout line AND mastic repair

[NewToPools_Texas]

Hello,

I have a pool that needs to have re-grouting between flagstone pieces, as well as new mastic. Can someone please help me understand what type of grout to buy (it's a beige/brown flagstone) and mastic. I see there is mastic that looks rubbery, as well as sand/textured.

I have no idea what product to use or how to apply it, but know I can't keep sinking $'s in to the repairs on this inground pool so have to take it on myself.

THANK YOU IN ADVANCE! Your advice/suggestings/links are so appreciated.

 

[AQUA~HOLICS]

Can you supply a picture of the grout that you are replacing?
The mastic is most likely Deck-O-Seal and the sand texture was accomplished by adding a light coat of sand to the surface prior to it drying.

 

[NewToPools_Texas]

Can you supply a picture of the grout that you are replacing?
The mastic is most likely Deck-O-Seal and the sand texture was accomplished by adding a light coat of sand to the surface prior to it drying.

 

[NewToPools_Texas]

Examples of "good grout" and the grout breaking away likely due to water sitting on it or its proximity to the pool

 

[AQUA~HOLICS]

From the picture it looks like a standard grout but if you take a sample of the grout to a big box store they would confirm the type.

 

[oldprophet]

Can you supply a picture of the grout that you are replacing?
The mastic is most likely Deck-O-Seal and the sand texture was accomplished by adding a light coat of sand to the surface prior to it drying.

That looks like Deck O Seal with sand added to it. Here in SoCal the separation In the mastic is caused by ground movement.Also the gap needs to be filled with sand or something else before the mastic is applied. Greetings to a fellow Californian!