mbar,

I guess I actually didn't ask any questions, I was just thinking out loud. I don't have a very big outbreak of algea and luckily my pool didn't get away from me.

If my chlorine didn't disappear to 0 or very low, hasn't the algea been killed? When you were fighting the algea battle where you losing only a small amount of chlorine at night or most of it? I have fought with it and have had no chlorine by morning - that's why I ask.

Since the chlorine didn't go below 3 and my stabilizer is probably around 35, isn't all my chlorine above 3 killing anything it can? I put enough chlorine to last a night and a day of sunshine.

I know of 2 reasons for shocking a pool 1) breakpoint chlorination which I know isn't practiced here and 2) put enough chlorine into the water to kill the organisms and make sure there is enough chlorine left over so that you're assured a kill (and yes it might take days to accomplish that kill if chlorine gets too low). Why go to 15? Is there something else I'm missing?

waterbear,

I understand the color thing and yes at times I can't tell the difference between 1, 1.5 or 2. But I usually can tell the difference between 2, 3 and 5. Maybe other men can't and maybe as I get older I will lose this ability so I will have to go to the K-2006.

As far as the precision of the testing, why do you need to be that precise?

I know that that as CYA rises you need to add more chlorine but is there really a difference between 5 PPM and 5.5 PPM at a CYA of 30 or 100. I would think that if you were close to a important level that you just add more chlorine for a safe measure. If I almost halved the water and I almost got to a reading of 3, well I'm about 6 - I don't see a problem unless you wanted to precisely add enough chlorine for breakpoint chlorination but like I said - add more than just enough.

With CC, I thought that the only time you test it is when you lose large amounts of chlorine and you need to break the CC before it starts smelling? I was under the impression that the belief here is that sunlight destroys the CC. I typically don't test for CC in the pool after Ben stated that and whenever I have I had none.