Wow, I love pool school! On July 22 I began testing my own water and need some reassurance from experts that I'm on the right track. I'm sorry this is long but there is nobody in real life who I can have this conversation with, and my boyfriend frankly does not listen to my chemistry dissertations anymore, although he fakes an interest.
First time pool owner. I bought my house/pool last December. Pool is 3 yr old, 18,000 gallons, in ground, plaster with sandstone tile surround, Aquapure SWG, Hayward sand filter. The previous owners left me the original pool book with instructions to "add salt to keep reading between 3.0 and 3.4". I had a pool company do a pre-purchase inspection and also talked to them about maintenance. They said "Salt water pools really don't need maintenance, keep this reading around 3". So far, so good. After purchase, had original pool builder come out to teach me to maintain the pool. They showed me what all the pipes and valves did (I wrote on each pipe with a sharpie--not attractive but very helpful!) and how to work the SWG and pump. OK, now I'm ready to go. Pool is not winterized or covered here in Louisiana, so pump ran all winter on timer and water remained crystal clear while I blissfully ignored it. (Note: they did not test water, nor tell me I needed to. I know. I know.) SWG was set at 20% all winter, per their instructions. Told me to raise it to 40% when the water warmed up.
In April the water was warming up enough to swim, in high 70's/low 80's, I set SWG to 40%. Swam and enjoyed the pool for a couple months--it's not a high use pool. Added a bag of salt once when the SWG readout was 2.8 and it moved back up to 3.2. I will embarass myself here by saying that I THOUGHT that the 3.2 readout meant that my pool had appropriate chlorine, based on my "instructions".
By mid July, I thought the pump was not pumping well, evidenced by the water sprayers not spraying as strongly. I called the pool company and they came out, showed me how to backwash, and for the first time ever, tested the pool water! I watched with great interest. He said PH was "high" and chlorine was "low". He poured some MA in the pool and left me the rest of the jug. Bumped SWG up to 70%. And gave me a test kit. I had that week also noticed some small, pencil eraser sized algae spots on the built in pool steps and ledge and around some inset ceramic tiles on the steps. Maybe a few dozen. hmmmm. Scrubbed them off. So I get on the internet to see how to use this test kit and what to do about the algae. I find pool school. My eyes are opened. I use the pool-man kit for a few days then ditch it and buy the best one Leslie's has ("DPD Complete Chlorine Kit" rebranded Taylor k2005 I think--has Taylor book), and have ordered the fas-dpd chlorine test kit from Taylor.
Temps around 100-109 outside, pool water in mid-high 90's. Water reached 100 one day. Here are my starting results:
water temp: 94
pH: 8.0+ (Acid demand 4 drops, this is a couple days after he added 1/3 jug of MA)
Based on my pool school education, I decided to 1) get chlorine into the pool asap 2) add CYA, 3) get CH up, 4) keep pH down while all the above is going on and worry about TA after all else is in control. I used chlorox bleach, about 2 gallons total over a few days, kept SWG at 70%. I have steadily decreased my SWG to 25% because the chlorine reading was staying very high (diluted the water x3 and still over 5 range on the reader). I have to add at least 16+ oz of MA about every 2-3 daysto keep pH under 8. I've used one whole jug plus the remaining 2/3rds of pool-mans. After two weeks of working on these steps, I have readings today of:
Water temp: 97
pH: 8 (acid demand 2 drops)
FC: 3-5 (hard to tell, but it is finally coming back into "view" on the tester, from being hot pink for last 2 wks. Awaiting fas-dpd test kit)
TC: same color, 3-5?
So I added more MA today, and that's all. The algae spots have not returned. I need to get this high pH under control and don't know why it wants to stay around/above 8 all the time. I understand the SWG creeps up the pH, but this is more like a trot. Once I get the real FC test, I can calibrate my chlorine and my SWG. I will also then raise my CYA more but really want an accurate FC first before I do anything but add MA. My goals are FC: 3-5, CYA: 70, TA: 70, CH: 300, and pH: 7.6ish. OK? From day one, the pool has been clear and sparkly and remains so.
Am I on the right track? Why is my pH so hard to keep down? And thanks so much for Pool School and your forum!