I recently moved to a house that has a pool. I'm attempting to take care of the maintenance myself, but I have a couple of questions.
First, The pool had noticible algae on the sides a couple of weeks ago. Nothing on the surface as far as I could tell, but a green looking substance on the sides of the pool at and below the water line. I brushed off what I could, and used some algaecide and shocked the pool to 30ppm (using 3 gallons of liquid chlorine for my ~10,000 gallon pool). The algae came back the next week and so I did the same. It's been about a week since that and there is nothing noticable, but I have noticed that my chlorine levels are dropping. From shocking the pool with 3 gallons a week ago, today the chemicals are at:
1ppm Free chlorine
Calcium hardness 350
Cyanuric acid 32
I added more chlorine to bring it up to ~5ppm, but it seems like the levels are dropping quickly. I'm in Austin, TX where it's been in the 80s for a while so I suppose it is natural for the levels to drop quickly, but how much chlorine should I expect to have to add per week? In addition to adding liquid chlorine I have an in line chlorinator that has a couple of 3" tablets in it. My question is whether this amount of chlorine loss is normal, or whether there is still algae in the pool eating it up. And if that is the case, what other steps should I be taking and how do I know when it is gone for good?
My second concern is that when I turn the pump on, it pushes a lot of air out of the returns for the first 30 second which causes the water to bubble up and spill over the edge. There appears to be a leak on the lid of my chlorinator so I've ordered a new o-ring for this, but the leak seems fairly small. What could cause this much air to build up in the system when the pool is off? And can it cause damage when it's pushing this much air through the system? As far as I can tell everything other than the chlorinator seems sealed well, the filter isn't leaking and the pump itself seems fine.
Thanks so much!