Happy Memorial Day folks! I'd love to be swimming in my pool, but there are a few reasons we can't, even though it's just been a brutally hot spring here in Florida (there's that tropical storm too but we've seen worse.)
First, the setup for our family pool includes:
- Built in 1991
I believe Gunite material
Hayward C1200 cartridge filter with 1-month old cartridge from Leslie's (the core has rectangular opening for water flow)
3' In-line chlorination tabs from Pinch a Penny (the ones with the blue specks)
MX8 Barracuda hooked into skimmer line as I couldn't find an adapter for the dedicated drain line that would keep the hose in place
About 2 months ago, we could not for the life of us get the pool in a crystal clear blue state. After shocking with Leslie's Power Powder Plus and replacing the filter cartridge, we finally were able to clear things up. Chemistry in the system came back perfect according to their in house guidelines including phos levels at 0 (as a side note, they wanted to know if I was using their Phos Free liquid to which I said no. They were shocked, hah!) However, I've attached photos of the staining left behind.
I spoke with the folks at Leslies and performed the vitamin C tablet test. No reaction lead me to believe it was not metallic and therefore gunky stuff left over from the pre-clear state. We went back to Leslies this weekend and explained our situation. Ended up walking out with 2 5oz bags of their Yellow Stop powder plus 4 bags of Power Powder Plus. As of this writing, we're wrapping up the procedures that they provided for us in attempting to remove the stains.
Here's the problem. Even with a metal brush, those stains in the photos above are not going away. As I scrub, all I see is some white powder being lifted off the stairs, which quite frankly scares me a bit.
Question 1: If those photos are clear enough, are those stains organic materials that won't go away easily, ala black algae?
Question 2: I know the pool is 21 years old and, at least to my knowledge, has never been resurfaced, acid washed, etc. Given the answer to question 1, is it perhaps time to resurface the pool? I believe no work has ever been done on both the pool and the pool deck (which is now cracking.)
The only reason I believe those stains are organic is that my pool filter will clog up within 24 hours. As an example, this morning around 10 am, the cartridge filter was cleaned. Baseline PSI for the filter is about 12. By lunch time, the PSI was up close to 30 with a lovely green film coating it.