Cracks and Leak in Brand New Pool

[PoolDoc]

Sorry, forgot one:

(h) Hire the best local builder or repair contractor you can find, and have THEM evaluate the problem.

and one more . . .

(i) Don't assume that your builder is TRYING to rip you off (so be polite), but don't assume that he's NOT trying to rip you off either (so be insistent on preserving your rights).

[Marin]

Ben makes good points, all of which you need to follow.

This is not your problem to solve, it's the builder's. If it's truly 2"/day, I wouldn't accept patchwork repair.

About the algae under the waterfall, I see this more often than you'd expect under natural rock waterfalls. My assumption is that the water is pulling a contaminant from the rocks or from between the rocks and depositing whatever's necessary to get the algae going. We did a job earlier this year with the same issue. They'd let the algae sit long enough that the plaster was seriously pitted and rough in that exact area. Everywhere else was pristine. Rather than replaster an entire pool over 10% that was bad, we were able to grind it smooth with a diamond wheel. All that said, I don't know what the fix would be to prevent it from happening again, other than to stop using the waterfall (route my clients took).
Another thing, leaks are sometimes not in the obvious location. That crack is suspicious, but it very well could be a return pipe that some worker forgot to glue (happens).
Good luck & keep us up to date. Share some pictures if you would please.

[pool2013]

Very much appreciate the feedback and guidance! Interesting about the algae. The water temp has jumped a lot in recent weeks which could help explain why it just started as we have had 0 algae issues until around now. I am able to get the algae off with a mask some pressure water from the hose and a lot of underwater elbow grease scrubbing. I'm going to try shocking the pool to see if that keeps it from coming back within the day.

To the bigger leak issue, not sure if I am posting pics correctly but below is an attempt. You can see the crack running down just left of the corner. The pool contractor did a dye test and confirmed the leak was in this location and that is it pretty severe. They are contacting the concrete company and are supposed to get back to me this week.

The pool contractor did the start up and maintained the pool until early June. I've been dilligent with it since then and have kept weekly records including a late June water sample analysis from Leslie pool. Going to get another one from them today and will get the test kit you recommend. (I have been using the one that came with the pool until now) The PH has been running at the high end of the range but I hear that is normal for new pool with a salt system. I've been careful about adding acid diluted in a bucket as per the instructions. Can't imagine any chemistry issue would casue a pool to fail in 8 weeks but to your point, want to have all bases covered just in case.

Again, I really aprpeciate the help and will keep you posted on how it goes.

[PoolDoc]

pix fixed.