Refilling my inground pool; want to get my water chemistry right

[nefretrameses]

OK, so the CYA test is the most difficult because it's not a color change, but a disappearing dot. If you haven't done so, go to the Taylor website and view the demo videos for this kit. Mix the CYA test solution and shake for a good minute. Let it sit while you do your other tests. Hold the vial at your waistline facing the sun. The dot must disappear completely from view. You can pour the sample back into the mixing bottle, shake again for a few seconds an repeat the test. f you did this, mix your pool water with DISTILLED water 50/50 and repeat the test. Multiply your result by 2. This is MOST IMPORTANT to control algae since the amount of FC you need to fight it is directly dependant on CYA

If you have CYA > 100 and algae I would raise FC to shock level in the best guess table (25 ppm for CYA>100) and keep it there consistently throughout the day until the water clears up or you get other advice from Doc. If this algae easily brushes up into a fine powdery cloud and mostly is on the shady side of the pool, it may be mustard algae and you should use the shock+ levels. Run you pump 24/7. 4 hours is OK in winter, but I generally run my pump 8 or 9 hours in summer.

Don't panic and add any crap from Leslie's without Doc's OK (or one of the other Mods). They often contain copper or other metals that clear up algae, but will cause other problems afterwards (stains, green hair, high chlorine demand, etc.)

You did not post the results of the other tests: FC, PH, TA and CH. These things can affect your finish. See my thread "Sand in the bottom of my pool". In particular, low Ph will cause damage. Raise Ph with 20 Mule Team Borax from Walmart's laundry aisle. If your Ph is 7.2 or less you should do this NOW.

So:
1. Raise FC to shock levels and keep it there.
2. Run your pump 24/7.
3. Test again and post results.
4. Adjust Ph if less than =7.2.
4. Use POPP (Pool Owner's Patience & Persistence)

Check your Ph before raising to shock levels. High FC (like >10ppm) can make the Ph test read high.

Marcite - Are they thin spots or stains do you think? Consistently low Ph ( like off the scale low) could do this. Are the spots near a return? Doc may want to move the finish issue to another thread.

Main drain. How old is the pool? A main drain may have been plugged and abandoned if there is a leak in that line. You said the pump cavitated, which results from trying to draw water from a closed pipe. Could it have just been air in the line that had to clear? Sounds like it, since it's now working. Monitor your water levels for an unusual or excessive drop beyond evaporation (which can be significant around here).

Hang tough, you'll get it, then it's easy. My pool never looked better since coming here.

According to the pool calculator (www.poolcalculator.com) you need 264 oz. of 8% bleach to raise FC by 10 ppm in you 17,000 gal. Pool. Thats 528 oz. To get 20 ppm. (4+gallons). Algae killing will use up chlorine, so you have to stay on top of it and not let FC drop during the fight.

Gallon calculation for a pool are notoriously wrong. You pretty sure about the 17,000?

John