Our inground pool was just completed in July, and although my husband says "we," it's actually just "me" that is looking after the pool. I'm so glad I found this forum through Google.
The pool builder left me a Poolmaster Basic5 Test Kit, and most days, I've tested for Chlorine, pH, Acid Demand, and Total Alkalinity. (Why is it named Basic5 and test for only 4 things?) Anyway, I've ordered the Taylor Complete Kit and it's due to arrive this afternoon.
I've brushed almost everyday, I may sometimes miss one day out of 10. The water is always crystal clear, the readings are almost always in the Ideal range, except for pH sometimes running a little high, so I put in the amount of muriatic acid that the test says to put in. I've taken samples to Warehouse Pool to have tested about once a week to see if our readings match, and so far, they have. Their other test says the Calcium Hardness is Low, about 175, and to add 5lbs of Hardness Control, which I've done. They also keep saying that the Phosphate level is high, but the pool builder has said not to do anything about that. And I've read your forum where several people have said the same thing, that if the FC is good, it'll kill the algae that high phosphate encourages.
When the pool was first finished, the white plaster was pristine WHITE!! Then about two weeks later there was a small grey circle about the size of a dime on one step. Since then, about 7 or 8 such circles have shown up, always one by itself in various parts of the pool, no clusters. Also, the spillover spa does not have these grey spots, but the bottom does have brown stains.
The pool builder came back to look, said the grey spots are not algae, and the brown stains are just stains. He didn't give me any advice on what to do to get rid of them, just said it's an ongoing process. There are also some brown stains in the pool itself, they all look like how a dingy bath tub will look if no one cleans it. I can't take pictures now because the sun is shining on the whole area, and there's too much glare. Will do it later this evening. The grey spots and the brown stains do not brush off. I have also bought an algae pumice stone and a wire brush to brush, and nothing comes off.
Once a week, on Thursdays, I've set the SWG to Boost at 100% for 24 hours, like the manual suggests to do, normally it's kept at 60%, been running the filter 12 hours, this past week only 10 hours since it's cooler. We had a couple of cooler evenings last week, so have heated the pool to 88°F for a few hours only on those days.
What are these grey spots, and brown stains? I've read through the posts and at first thought they were algae, but from what I've read, and from what Warehouse Pool says, algae will brush off. These don't. I think this morning there were a couple more grey spots at the bottom of the pool, smaller than the size of a dime, making a total of about 10 spots.
I told my husband about the Vit C tablet, so what does he do? Two nights ago, he went and got a 2" plastic pipe, stood it on its end and kept the Vit C tablet on one grey spot overnight. The next morning, there was a 2" ring of brown around the grey spot! The grey spot is still there. We tried rubbing the brown ring off with the wire brush, it is lighter but hasn't come off.
Sorry this is so long. Please help! This is our first pool ever. What can I do about these 2 problems at the bottom of my pool?