I recently purchased a home with a pool that had cloudy water. The previous owner was elderly and pretty much just fed the pool steady diet of chlorine tabs and did little else to the pool. Initial Testing revealed very high CYA. I posted the results here and received some advice on the next steps. I drained approx 75% of the water to bring the CYA to accceptable levels. As the pool was draining I noticed a grit in the steps / walls / floor & began brushing & hosing off the walls as the level dropped. I ran the filter continuously during the draining process keeping a close eye on the filter pressure and cleaning as required (Every 1-2 hours) The filter was always clogged with a green-yellow film and the gritty substance. I suspect that this is calcium but have not had a chance to get out to get some muriatic acid to test it. I have also noticed that the grout in the tiles at the water line seems to be thinning and a couple of tiles had fallen out.
I have included a photo of some of the grit I collected from the bottom of the pool along with a photo of the pool wall & tile
What are my next steps?
Continue brushing & hosing while running the filter until most of the grit is gone?
Refill and Slam?
More agressive cleaning methods?
I really want to get water back into this thing as soon as possible, A little nervous about the 75% drain.
Results of the last test the day before I started draining. I used the modified test to measure for the higher CYA levels