pH above 8 15ft X 48in Intex

[Pappy]

Is a quarter cup of 99% CYA a reasonable place to start if there is none in 4500 gallons? pH8+?

[PoolDoc]

CYA is about 2# / quart. 1 lb will add about 20 ppm to your pool.

So, no, that's not enough. Put about 2 cups in an old sock, and hang it in front of the return.

[Pappy]

Why not pour it in the skimmer and let it sit in the sand filter til it disolves? I need to wait a week between doses don't I?

[PoolDoc]

Most people have to backwash their pool frequently when they start it up -- and end up losing their CYA. If you're sure you want need to do so, go ahead.

[Pappy]

Added 121 oz 8.25 bleach to the pool at sundown. Just checked cl. I'm getting 2 or a little more FC and 5 CC. My pH is as I suspected, probably astronomical. I added 4 drops of the red stuff instead of 5, so it should have shown a lower pH than actual. Still LOOKED like 8.2. I gave it another jug of bleach.

I guess the plan is go get the CYA tomorrow after I confirm my theory that FC will be zero and CC will be who knows where. Stick some in the pool to get the pH to a measurable point. If I understand correctly, the CYA actually inhibits the effectiveness of the chlorine so it is desirable to keep CYA low til the pool is stable overnight.

[PoolDoc]

With which test kit are you testing?

[Pappy]

We currently have a "Pool Shop basic 5 test kit" from Home Depot. It is the drops but reads only to 5ppm chlorine. It says FC is what you see between 2 and 3 seconds and CC is >2 minutes. I'm going to wally world today to get the HTH kit so I can monitor CYA levels.

We got about 1-1/2" of rain last night and this morning the pH showed 7 - 7.2??? Can rain bring pH down that much? FC was in the 2-3 range. It's supposed to be cloudy today, should I dump another jug or wait til evening.

[PoolDoc]

Rain can have a low pH; whether it can lower the pH in your pool depends on the buffer level (total alkalinity). it's also possible the rain has not mixed with the rest of the pool. I'd wait & retest before trying to adjust the pH