Hi all! I have been running my SWG for 5 years and never had to fool much with my pool chemistry at all, but the cell died this winter leaving me a huge mess to clean up in order to open the pool...Until I can re-plumb for the new SWG cell, I'm running Tri-chlor tabs with Cal-Hypo for the occasional shock/FC booster, and have had to get myself educated to a whole new sanitizing process...
Anyway, that's how I found TFP...I have really enjoyed many of the posts, as I tend to really enjoy getting a lot of nitty-gritty details. In reading posts, though, I've developed several "I now know just enough to be dangerous" questions that I can't find answers to easily:
1) Some folks seem to post that they have/maintain FC levels well above 10 between regular maintenance cycles...or at least while they're shocking algae and watching for overnight FC drops....I was of the impression (from pool store guy) that FC>10 was problematic for bathers, as it could penetrate skin at that concentration (osmosis, I guess?!?) At what point is FC level too high for bathers? Is the reason for waiting to swim after shocking due to the need for FC to drop, or just to allow shock to disperse fully, so that bathers don't encounter stratospheric FC levels, or just to avoid being in the pool during really rapid oxidation phases?
2) I use a Taylor-2005 kit...and it only measures FC up to 5...using R-0001, R-0002, and R-0003 reagents....Are those the same reagents mentioned on the site that are used to test higher FC levels, and I just don't have a good enough color comparator, or would I need diff agents to test above 5?
3) I was totally surprised to hear in some posts that CYA apparently works differently than I was led to believe for the past 5 years...If FC levels have to be higher with more CYA in order to have the same sanitizing effect, what is the real "purpose" of CYA...does it really do anything helpful (e.g., is the CL that it "Locks up" eventually "unlocked" if it's really needed for sanitizing?)? In other words, is CYA really needed at all, or does it just give pool owners a false sense of security thinking that they have some FC when they really don't?
4) Backwashing/Cleaning CYA away -- Before TFP, I'd never heard of getting rid of CYA being a problem, as I have to replace my stabilizer seemingly every year! I once heard an old-timer near me opine that CYA tends to congregate on a DE filter...and not just during its initial (long) dissolving process....and that it can be pretty easily washed away from even reasonable amounts of backwashing. Has anybody else had that experience?!? Granted, my low CYA issues on opening may be because of ammonia issues (long story, but I'm usually really lazy with maintenance during winter months, and ammonia is possible...though I've never tested for ammonia) or it may be because I lose all of my CYA when I really clean my filter grids at the start of every season...I have noticed that if I take the filter apart and really wash the grids mid-season (e.g., post a massive algae bloom that always comes when my mother-in-law has large parties while I'm on vacation!), I always lose CYA big-time...so the rumor about CYA congregation on the grids seems to hold some merit in my experience. Anybody else have similar experience?
5) My CH is really low right now (not sure why), but I think that's a good thing since I'm just starting to use Cal-Hypo as a shock/source of FC. Will Cal-Hypo have the positive side-effect of actually increasing my CH appreciably? Some folks's posts seem to suggest so...
Thanks - I'm really anxious to hear everybody's thoughts on the above!