I am a new pool owner, and as so many others before have said, this is an invaluable resource to people like me, and I can't thank you all enough for making this information available. I've been lurking for a few days and just reading reading reading, and it's been wonderful. I already feel so much more in control of my pool, despite the issues I'll address below. So thanks!
First, I should say that my pool appears to have not really been well taken care of by the former owner. I think it may have been at one time, but the house was a rental for the last few years and things clearly had gone downhill. When we went to open the pool a couple weeks ago it was a hot mess - several dead frogs in various states of decomposition, hundreds of tadpoles and frankly it just looked like a big pit of dirty toilet water.
Not knowing the first thing about pools we called the pool guy the former owner had recommended. He came and charged us a few hundred bucks to assemble the filter and throw a bunch of shock powder in the pool. He couldn't even catch the sole remaining bullfrog. I had to do that. He had serviced the pool over the last few years, so you'd think he would have been forthcoming about some important information, such as how he closed it last year with a layer of leaves and debris still on the bottom. Or, how the long flex PVC from the skimmer to the pump ran exposed behind the pool house and had several dozen holes in it, causing us to waste days worth of water trying to keep the pool full.
Anyway, since I took over maintenance and started reading here, I've replaced about half the suction side plumbing with rigid PVC to eliminate the visible leaks. I see there seems to be an ongoing debate on rigid vs. flex, but no more flex for me as I've seen first hand how it can wear. So far the new plumbing is holding up well and there are no signs of leaks. Unfortunately, there are another 20 ft. or so of flex PVC running under a concrete slab to the skimmer alongside the pool. The symptoms I'm having that lead me to believe the suction side leak remains are as follows:
a) significant air coming out the return
b) significant air in the pump basket
c) decreasing pool water level (fairly substantial at 1/4 to 3/8" per day)
d) significant sediment/sand settling on the pool floor that I can't seem to remove - increasing daily
e) small pebbles at the bottom of the pump basket
The remaining flex hose is laid in sandy/rocky soil below the concrete slab and I suspect a significant leak that is drawing in the surrounding earth/pebbles which are ending up in the pool and pump basket. It took me a few days to figure this out as I thought I had resolved the leak issue by replacing the flex hose that was accessible (not under concrete).
Anyway, I guess my question is has anyone seen these symptoms before, and can it be confirmed that this is the likeliest scenario for sand/pebbles ending up in the pool/pump basket?
Finally, thanks to pool school I did the overnight test last night/this morning and found a .5ppm loss of FC overnight but a CC level of about .6ppm. I used the 25ml test for greater accuracy because the 10ml test was giving me .5 CC and 3 FC, but the 10ml was giving .6 and 2.5. Should I still shock at .6ppm CC, or am I done? Water is crystal.
My full test numbers are:
CYA - 25-28 (Low, I know, but the pool guy put tabs in the chlorinator, so I expect this number to rise still - and I wanted to proceed cautiously with the CYA)
FC - 3 (added some CL this morning after the overnight test to bump this up a bit)
CC - .6 or .5 depending on 10ml vs. 25ml test
TA - 70
pH - 7.3
CH - 30
Water - crystal clear, extremely faint CL smell
Apologies for the long post and thanks again to everyone for such a great resource.