I just bought a house about two weeks ago that has a vinyl inground pool that is 30,000 gallons. It uses a DE filter but I'm not sure about the flow rate. The house is in Southern New Jersey. The pool uses two floating chlorinators and chlorine pucks. When I first moved in, the chlorinators were in the water but when I checked inside them about three days after moving in, I realized they were both empty. The pool was clear but I did notice some algae growing on the steps and along the seam between the steps and the pool wall. I bought chlorine pucks and put three in each chlorinator.
A couple of days later, I noticed a lot more algae so I took a sample of water to the pool store and had them analize it. They told me there was a lot of phosphates in the pool that was feeding the algae. They gave me a bottle of phosphate remover and some product to shock the pool, but I'm not sure what the product was. Anyway, they told me to add the whole bottle of phosphate remover and put in eight bags of the shock product (1 lb each). She also told me to add two bags of the shock product once per week.
The next morning the water was mostly clear, the green was gone, but there was a lot of white of stuff on the bottom of the pool, which I believe was dead algea. I've gotten most of that stuff off the bottom by vacuuming to waste and refilling the water as needed. The water is now perfectly clear. Taking the pool store's advice, I added two bags of the shock product yesterday morning (one week after my last shock).
I've been on this forum, learning what I can. I just ordered the Taylor K-2006 test kit and did some testing last night. Unfortunately, I couldn't test everything, but here's what I found:
Free chlorine: 7.5
Combined chlorine: 0
Everything looked good until I got to the CYA reading. I think my free chlorine was high because I just shocked the pool less than 12 hours prior. My question is why my CYA was 0?
To do the test, I added 7ml of pool water into the CYA test bottle and then added 7ml of the CYA reagent. The instructions say to then transfer the "cloudy water" to the smaller test tube with the black dot on the bottom until the black dot is no longer visible. My water was not very cloudy and after I filled the tube all the way up, I could still easily see the black dot. Assuming I did the test correctly, my CYA would be at or near 0.
Can anyone comment on my results?