We have had our fiberglass, 10,000 gal pool almost 5 years. It is CRYSTAL clear. I mean SPARKLING, but I am struggling with a few of things. Break down of my last test that I did with my test strips:
CH - 250
CC - 1
FC - .5 < 0
pH - 7.6
TA - 240
CYA - 150
TDS (Based on in store testing Tuesday (8/14) - 3000
My CYA has been high since install in 2007. They forgot they already put it in and put it in a second time. I've never added any since.
We have solar panels that heat the pool and it maintains about 92 degrees F. There was this odd debris in the pool that was either seeds or eggs (VERY small) that no one could identify. It would settle on the steps, bottom and sides but easily brushed right off with barely a touch of your hand. I would vaccum it up with the normal manual hose vac and they would return covering the pool in a couple days. I vaccumed up with a robotic vac and the smell was very fishy smelling. I pulled a full teaspoon of this out, hosed out the rest, and took it to the pool store. Still couldn't be identified. Again, crystal clear water. So I had the sand in the filter changed out on 8/7 and they said it didn't look odd at all, but the little brown specks seem to be going away now. When I backwash the filter the water is really white before it runs clear and leaves a white residue on the concrete. This is even since the sand was changed out. I have to assume this is caused by the high TDS??? Water tastes very salty. We have a lot of landscaping around the pool, but no leaf dropping trees. Living in NC we do not close the pool in the winter and just leave it running. The filter is run 24/7/365. There is no run off that goes into the pool. We live close to a farmers field, but probably more than 2 or 3 football fields away. Guy at Leslie's said the level of salt is almost like someone intentially put salt in your pool. I have no reason to believe anyone would do that.
Next problem, I cannot get my FC up. I was told that the shock I was using that had SODIUM DICHLORO-S-TRIAZINETRIONE in it (Bioguard Smart Shock), in conjunction with my chlorine tabs is helping to drive up the CYA and could be blocking the FC. It was suggested to stop using the tabs and just shock the pool with Calcium Hypochlorite instead of sodium dichloride. Monday I used one bag of Leslie's shock (forget the name). Didn't raise the FC at all. Tuesday I put in 2 bags of Power Powder and it seemed to raise it a little, Wednesday I put in 2 more bags of Power Powder but it doesn't seem to have helped much more. I'm not using any chlorine pucks at this time. With that said, my chlorine level is the best it has been in a long time. I also struggled to keep chlorine and go through more than 7 3" pucks a week. I assumed that is due to the temp of the pool and sun.
With these issues I'm at a loss. Never had any problems in the past other than keeping pH up. I am always add pH up to keep it above 7.0 and chlorine up. I'm also worry about the safety of using the pool. While there isn't a spot of algae, can there be other bacteria that I need to worry about? And I worry about damaging my equipment. The pool guy at Leslie said it is fine and actually joked that I could easily switch over to a salt water pool with the concentration of salt I have now. Thoughts???