Hi all, I have a 27k gallon in ground gunite/plaster pool with elevated spa. We had the pool installed ten years ago by a respectable builder and this year it's in need of some attention. Recently, we had some nice weather that stimulated algae growth (first time this year) and I immediately struggled to get FC levels above 2ppm when measured with an OTO test kit. This was after 5 gallons of 8.25% best value bleach and 4 shock bags of 60%
Last week I tested the chemistry with a Taylor 2006 kit and discovered that the CYA is up around 200ppm! The hardness is also up around 800ppm so its time to drain and refill. Last time we did that was at least 5 years ago to fix a leak in a return line.
Since I am replacing at least 80% of the water in the near future I figured I should also repair some plaster cracks while the water is out. I had a good friend come over today that works on pools for a living to tell me about hydrostatic valves/dangers of draining etc. but what caught me off guard was that he mentioned that the cracks were in the gunite and would probably need stapled/epoxy injected.
I've attached images of the cracks. Black Algae is making them look more obvious but you'll get the idea. One is from tile down around the front of the hot tub and the other is from tile down to a light fixture. I have lots of questions but the biggest one is this "the builder guaranteed the gunite shell for life so if these cracks are into the shell are they liable to fix this problem and patch the repair?"
My original plan was to drain, chip out some plaster cracks and fill them with pool patch etc. and maybe while I was at it, sand down some pitted plaster sites. This seems like it won't be sufficient if the cracks are in the gunite. Any advice? Are these cracks superficial or am I in for an expensive repair?
Thanks in advance, Kris (Austin, Tx)