Apologies if this is a little long. Our pool has been up for about 3 weeks now. I had clean river water brought in to fill it as the tap water was pretty dirty from the supply(I'm in a small farming town on the coast of Peru). For the first week I couldn't keep chlorine (using granular) in the pool no matter how much I used and I ended up with algae (green).
After finding this site and doing some reading I thought I found the problem - total alkalinity. Using two different test kits (not great products I know) the alkalinity was off the chart. Using the strip test(AquaChek) it was over 240. pH was over 8.4 and chlorine was pretty much always reading 0 except for right after adding some.
Following the suggestions on this site, I used a product available here (they call it muriatic acid) with 9.5% hcl. Can't get anything else due to regulations because of drug manufacturing here. I used a lot of it but finally got TA of 120 and pH of 7.2. Aerated to bring Ph back up a bit. After shocking (using granular)the FC stayed up at 10 or higher for several days. Now however I have an almost clear substance floating on the top. Not solid but millions of tiny particles(?) remaining somewhat separated from each other(ie. not forming a solid mass). I rigged up a skimmer and can remove the film but it comes back over night. Some dark matter is sitting on the bottom of the pool this morning also. VERY dusty here but not sure that's what it is. The water itself is nice and clear. No irritation or burning in the eyes. The readings are now; FC:5 pH:7.8 and TA 180sh. Are the particles floating on the top algae? No staining. Any help would be appreciated as there is certainly none available here. Pools are not common here at all, let alone Peru in general, so there is no experience to draw from.