hwwjr71 said:
Does the high CYA have a major effect on the FC loss?
Major isn't the word for it. Your pool at that level will need to target around 18ppm of chlorine every day just to make it through the day w/sun and bathers. And that's only if you have no algae issues. On the best algae free day you should expect to loose 50% of your chlorine. At high CYA levels like you have (it very well could be much higher, the testing is not accurate much above 100ppm) that means you'll loose 9ppm per day... every day and will need 9-11ppm sitting in the pool at all times (inactive chlorine).
9ppm/day is for a 1000 gallon pool is just under 1.5 gallons of 6% bleach. How many gallons is your pool? If you're at 2000 gallons that means you will need 3 gallons of bleach a day just to stay sanitary.
The CC reading you got is not valid. Ignore it. You have visible algae, you need to shock.
See pool school. Read it a few times, focus on the algae section. Read it again. Focus on the shocking process and read that again... again... Take to heart the concept that shocking is not a product or a one time action, but rather a process that has to be completed. You can't throw stuff in and walk away expecting miracles.
Get a proper FAS-DPD test kit. Leslie's can't be trusted to sell you the correct one and you can't be sure you will be at shock level, or complete the shocking process without it. (you can of course luck out, but you won't know till you fail or succeed. Would you put a possibly broken part into your car... just in case it worked?) The TF100 is the best deal around and shipping is amazing fast. See
http://www.tftestkits.net
You will need liquid chlorine, either 6% regular un-cented no nothing special bleach, or you can buy 10-12% liquid from a pool store. Either works, about the same price.
You also will need to drain and refill a total of around 70% your pool to get it to a manageable CYA level. With it that high, you'll want to drain part (30-50%).. refill... drain part (another 30'ish)... refill... test for CYA... etc. A sort of dance that will get you down to a CYA level that won't take 33ppm to shock, and 11-18ppm per day minimum maintained chlorine level.
40-50ppm CYA is an average sunny location number to aim for, but if you're going with the SWG you can drain and dilute to 70-80ppm instead (SWG's run best on a slightly higher CYA level than liquid chlorine only pools).
Other than a green swamp, the most common issue with those looking for a solution to their pool battle is high CYA. Tablets, dichlor shock products/chlorinating both add CYA every time you put them into the pool. CYA doesn't go away, and chlorine demand increases and increases till it's impossible to even attain the required level with the products that produced the high demand.
Oh, almost forgot. Get friendly with the pool calculator
http://www.poolcalculator.com you will be using it frequently.
