Hey yall, here's my story...
Bought my first house last September with an IG pool. Pool is gunite, 18k gallons, chlorine, Nature 2 express, cartridge filters, no heater, no spa. The person I purchased the house from recommended the local pool shop down the road to test my water. He told me that he had simply just gone to them ever since he had the pool put in. I'm not sure the exact age of the pool, the house is 1999 and I think the pool was put in a few years after so maybe it's about 7 years old. The pool was in perfect shape and still looks to be about that way. The pool store said he always kept it in check and judging by the rest of the house I believe them. So I went along with the bring it in and have the store test it last fall and come about October they said that it was now cold enough (I live in Atlanta) to basically not worry about the pool until it got warm again. So I did just that (aside from keeping it from freezing). The pool wasn't closed or drained or tested in the winter. So early April I start bringing samples in. I remember the first time I went in they had me dump either 10 or 25lbs of Calcium, so Alkalinity and so on. So I know Calcium was low, just not sure what it was because they never tell me levels, it's just buy this and you'll be great. Anyways, I kept going there every week or so until my Algae issue. I had a very small amount of mustard Algae on the walls one day and went to the store where they gave me a quart of Copper Algacide and told me to dump it all in. I went along and it did the trick with the Algae but then slightly stained the gunite blue/brownish. Since then the pitting in the concrete has showed up more as it's now highlighted (so I've started paying more attention to it). Needless to say I wasn't happy that my pure white pool was now stained so I started reading this forum and am now doing everything on my own. I've bought the Taylor 2006 kit and have kept everything in perfect check. My pH has never been lower than 7.2 or higher than 7.8 since I've been testing. My trips to the store before self testing always yielded a "looks pretty good just add a little acid or a little alkalinity up". My numbers right now are this
Now when I started testing about a month ago my CYA was near 100 but I stopped with the Trichlor pucks and have been using bleach. Also, my CH was steady at 200 which the pool store said was fine but since I noticed a little pitting I decided to up it to 290 a few days ago (was shooting for 300 but close enough). Anyways, just recently (last month or so) I've noticed small black marks on the bottom of the pool, there are maybe 2-3 visible from outside the pool and maybe 2 more so small you need to swim to the bottom to see them. None of them are bigger than a dime, probably half dime sized to bb sized. When looking close it looks like the plaster is worn through to another layer i believe.
So here is my long winded question. Does this mean I am going to have to resurface my gunite? This the answer I get when I search for this issue everywhere. Is it not okay just to do some sort of patch repair? I feel it's so minor how in the world could it come to this, needing a 3-4k resurface job? The pool seemed perfect and still looks almost perfect. I don't know if these marks were there last September but I have a feeling they weren't. Sorry for this long winded post I just wanted to get the whole story out. It just doesn't make sense that the plaster could be eaten all the way through already. Is it possible this all happened in the winter? I really wish I had discovered this forum back in September
Anyways, if anyone read through this mess and wants to offer hopefully what is soothing advice I'd appreciate it.