Let me start with a big thank you. Without what I have learned here my pool experience would be much worse. I just barely managed to avoid getting pool-stored and I now have nice water. Success eventually came from finally shocking effectively with bleach and using a slime bag to catch what my Intex cartridge filter couldn't. (You can read my story about the slime bag here: Slime Bag review
I am hoping the following saga will help other beginners avoid trouble.
We put up a 12 x 20 Intex oval frame pool Memorial Day weekend. We choose the spot in our yard that was somewhat private and relatively flat. The location doesn't get mid-day sun, so the temperature rarely gets to 80. The Intex kit was $400 at BJ's wholesale club. We spent about another $200 on loom and renting a plate compacter for leveling. We are pretty pleased to have a pool for so little money. Even this was a stretch on the budget.
We filled the pool with Billerica MA drinking water. I immediately added 1 Gallon of 12.5% bleach on Namco, a northeast pool chain store's, recommendation. They call it "Blue Shield Shock Treatment". This probably raised the FC level to 28ppm which might be a bit high for a vinyl pool.
When I asked about what else I should do given I started with Billerica water they said I needed to get the metals out. They sold me their "Blue Shield Mineral Magnet". Given how poorly Intex filters work this probably didn't do anything. The filter did catch lots of yellowy gunk that was probably pollen. I also used Namco's soda ash to raise the pH to 7.4.
A week later they sold me their "Blue Shield Alkalinity Balance Control". (This is probably baking soda they have slightly doctored so it isn't so obvious that is what it is.)
I started off using Triclor tablets in a floater, but they were dissolving quite slowly in the frog floater I got from K-Mart. Namco sold me a plain floater that worked a bit better, but even with five 1 inch pucks I wasn't getting enough clorine in the water. I was averaging about 1.5ppm when I tested in the morning. Once I stared putting the 2-3 pucks in the skimmer my clorine level somewhat stabilized around 3ppm in the morning, but I would occasionally drop below. (I now know I should have been testing in the evening after the day's sun has done its thing.)
I was feeling pretty good about Namco at this point and the pool looked great. I was a bit surprised by this given the trouble I had getting the clorine level stable.
On 7/7 I had some mostly green with tinges of brown and yellow growing on the bottom in one of the shadier spots. I immediately went to Namco to get something to kill green algae. They were out of green algae treatment and suggested I try a black algae treatment. I couldn't believe they would suggest an obviously wrong product. I passed and went to Leslie's down the street.
The first Leslie's employee suggested something that also required that you first raise your pH to 8, treat, and then drop you pH. That seemed like adding an awfully lot of stuff to the water. The second employee recommended something entirely different that was quite expensive. This left me believing more research was needed and I went home empty handed. I vacuumed the pool scrubbing pretty well and the filter cartridge did catch green stuff. The water started to get a little murky.
On 7/10 I added 28OZ of 12.5% bleach to shock based on what the bottle said. From what I know now this brought the free clorine level up to about 7 . ( Based on calculations and measurements done later on CYA on 7/19, I believe my CYA is in the 30 - 40 range.) This means I didn't quite get to shock level for my pool. The next morning the level was back down to 2 FC and 1 CC. I also didn't know I had to maintain the shock level.
I also started adding calcium chloride at this point. To their credit ,the Namco people didn't push this. I hadn't quite got the message that this was unnecessary for a vinyl pool. My hardness is now 100.
On 7/13 the algae was worse. Did another scrub/vacuum.
7/15 I added bleach at 10 AM and 8 PM. On 7/16 8 AM FC was 7, and down to 4 on 7/17 so this probably wasn't a really good shock.
On 7/18 more algae on the floor. I definitely noticed the water was murky after you stirred it up.
I added a full dose of PolyQuat 60 somewhere around 7/19 but I apparently forgot to log exactly when.
On 7/22 algae on bottom a bit better. I did another marginal shock.
7/25 another vacuum/scrub. The filter did catch some green.
7/26 1.75 oz maintanance dose of PolyQuat 60.
7/27 I was going away for a few days, so I shocked it but good. The 64 oz of 12.5% bleach probably brought FC up to about 15.
7/29 Evening my smart father-in-law says the FC is 7 using an Taylor OTO test with 50/50 pool/distilled water. This means I was at shock level for more than 2 days! He adds bleach that should bring it up to 9.
8/1 10AM FC 4. I have made it through the trip with good clorine levels.
For the next two week I burned about 2ppm clorine a day that I started measuring and adding in the evening. I was pretty sure the algae was dead, but my water was murky once it got stirred up.
I learned about the poor performance of Intex filter over in the equipment area. I added the washer to reduce bypass but it wasn't enough.
8/14 vacumed with the slime bag. WOW it caught a lot!
8/14 - 8/15 filtered with the slime bag. Again it caught a lot and my water is nice again.