Question about gunite pool bottom

[mostrander]

First of all love this forum you guys have already helped me out several times.
A Little history first, just bought a house with a 20 year old gunite pool that was never finished, no plaster. The walls and bottom are still bare gunite the walls are in great shape but the bottom had some deteriation in the gunite which I cut around and chipped out. To get the bottom redone with gunite will cost $6k so that is out of the question. I am going to pour concrete to re surface the bottom, here is what I'm planning on doing:
1.I have taken my diamon blade in the skill saw and cut a line all around the bottom about 3 inches up on the wall and an inch deep and chisled out the gunite.

2. lay wire mesh and pour 3 inches of concrete to cover the bottom.

what do you guys think and what is the best mix of concrete to order?

Thanks,
Matt