Water Chemistry

Test results, dosing, algae, cloudy water & stains

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Water Chemistry Discussions

Thinking about a sequestrant before my next fill, opinions Getting ready to drain a chunk of the spa water and refill, and wondering if it's worth dosing a sequestrant before the fresh water even hits calcium … Water Chemistry Karen Delgado Sep 6, 2026 3replies Draining a foot for calcium vs just living with the scale Fill water here is 400 plus straight out of the tap so calcium only goes one direction all summer. Been going back and forth on partial drains every y… Water Chemistry Karen Delgado Aug 31, 2026 3replies Didn't realize how fast the spa evaporates compared to the pool Been tracking water levels for the calcium post I made last week and noticed the spa drops almost as much overnight as the whole pool does, despite be… Water Chemistry Karen Delgado Aug 28, 2026 4replies Thinking about adding borates before i buy the stuff, worth it been reading up on borates for algae prevention since my swamp saga this summer, some threads on here make it sound like a game changer for keeping st… Water Chemistry swamp_tyler Aug 27, 2026 4replies Didn't expect my fill water chemistry to swing this much by season Topped off about 4 inches this week after the heat, then retested and TA had jumped almost 30 ppm from where it normally lands after a fill. Called th… Water Chemistry Marcus Reed Sep 2, 2026 2replies Didn't realize how much a tenth of pH moves my saturation index Been running the LSI numbers on my pool for years just to keep an eye on scaling risk, figured a tenth of a point in pH wouldn't do much. Ran it again… Water Chemistry Marcus Reed Sep 2, 2026 2replies Cross checking my ICO caught a bad reagent bottle Small one but saved me a headache. FC on the Taylor kit read 2.0 three days running even though I'd been dosing normally, meanwhile the Ondilo kept sa… Water Chemistry Priya Raman Sep 1, 2026 1reply Spa pH won't hold steady, drifts up within a day of dosing Pool's fine, steady as always. Spa is the problem child right now. Dose acid, get it to 7.6, come back the next day and it's already at 8.0 again. Spa… Water Chemistry Karen Delgado Aug 23, 2026 2replies Hand-dosing liquid chlorine vs a peristaltic feeder, still weighing it Been going back and forth on this most of the season. Right now I dose liquid chlorine by hand every evening, FC swings from about 3 up to 6 and back … Water Chemistry Alan Pierce Aug 25, 2026 5replies Bumping salt cell percentage vs just running it longer each day Been going back and forth on this one. My AquaRite's been holding FC fine at 60 percent output for a 5 hour run, but with the heat lately I'm chasing … Water Chemistry Marcus Reed Aug 26, 2026 2replies Total alkalinity crept up and now my pH won't sit still Been running trichlor and a weekly shock same as always for 30 years and never had this happen before. Tested Sunday and total alkalinity was up aroun… Water Chemistry Earl Simmons Aug 26, 2026 2replies Surprised how much a half point of pH changes my actual chlorine Been logging FC/pH/TA/CYA daily all season (yes I'm that person) and finally sat down and ran the numbers on hypochlorous acid percentage instead of j… Water Chemistry Priya Raman Aug 25, 2026 1reply FC dropping almost 3ppm overnight with CYA sitting right at 40 Been keeping FC at 6ppm and CYA tested at 40 with the TF-100, so that should hold pretty steady overnight with no sun eating at it. Instead I'm losing… Water Chemistry Alan Pierce Aug 22, 2026 2replies Waiting an hour after dosing before testing, small change big difference Small lesson but it saved me some head scratching. I'd dose liquid chlorine in the evening then test right away and get numbers that never quite lined… Water Chemistry Alan Pierce Aug 21, 2026 2replies TA keeps creeping up even though I'm not adding anything for it Been chasing this for about a month now. Total alkalinity keeps drifting up into the 130-140 range even though all I'm dosing is liquid chlorine, noth… Water Chemistry Alan Pierce Aug 12, 2026 2replies Calcium hardness reading jumped 60 points, didn't add any calcium Taylor kit's been steady around 420 for two years since I know my fill water. Tested last week and it's pushing 480 out of nowhere. Haven't added hard… Water Chemistry Karen Delgado Aug 17, 2026 1reply Liquid chlorine vs dichlor now that CYA's parked at 45 Been going back and forth on this all season. CYA's been sitting at 45 for weeks (screen enclosure means barely any splashout to dilute it, so it just… Water Chemistry Priya Raman Aug 16, 2026 1reply FAS-DPD drops never quite hit clear, just fade out on me doing my FC test with the K-2006 like always and normally i get a clean snap to clear but lately its just fading lighter and lighter and i cant pin do… Water Chemistry swamp_tyler Aug 13, 2026 1reply Anyone actually flush a cartridge filter with something other than a hose Cartridge filter, pleats keep loading up with calcium film faster than a hose rinse can knock out. I soak in acid now and then but that's a whole prod… Water Chemistry Karen Delgado Aug 12, 2026 1reply Caught a slow FC drift before it turned into anything, thanks to trend data Small one but felt good. Been logging daily and noticed my FC was drifting down about 0.3 a day for four days straight, nothing dramatic, pH and TA bo… Water Chemistry Priya Raman Aug 7, 2026 6replies Chasing LSI on the spa side, pool stays clear but jets keep scaling Fill water here is over 400 ppm calcium so I know the drill, run pH low, keep an eye on the Blue Stuff dose. Pool tile line stays clean doing that. Sp… Water Chemistry Karen Delgado Aug 10, 2026 1reply pH keeps crashing a day after i dose liquid chlorine, alkalinity's fine so the swamp's clear now, been running good for a few weeks, but every time i dump in liquid chlorine to keep FC up in this heat my pH drops like a ro… Water Chemistry swamp_tyler Aug 8, 2026 2replies FC won't hold overnight, pH steady, algaecide already ruled out Got a weird one, and it's my own pool this time not a customer. FC at dusk reads 4, next morning it's down to 1 or lower, every single day this week. … Water Chemistry tampapoolguy Aug 7, 2026 3replies My own pool's CYA crept up to 90 and I never added a single tab Kind of embarrassing since I test this stuff for a living on other people's water and forgot my own. Been topping off with liquid chlorine all summer … Water Chemistry tampapoolguy Aug 5, 2026 2replies