Algae Blooms Even Happen to Mods!

[Pappy]

Is it possible that high chlorine levels affect CYA test results? Kinda like high chlorine skews pH readings?

[CarlD]

That may be...Great Thought! Ben? Chem_Geek?

[chem geek]

Very high chlorine levels can in theory bind to enough CYA to interfere with the CYA binding to melamine, but that would cause it to read lower, not higher. Some people say to use a chlorine neutralizer to avoid this, but it doesn't seem to be that necessary.

On the flip side, if the water has suspended particles, it can create more visible precipitation in the test so it's best to test the CYA level when the pool water is clear, though for people who didn't test before and have an algae bloom they don't have much choice.

So as you can tell, I don't have a good answer for you.

[CarlD]

Actually, Rich, you do give me a clue. The CYA measured around 70 before I left on vacation, was 40 when I first measured it with the bloom, with an FC of 16.5, then measured 60 with an FC of 19. In both cases the water was, of course, cloudy.

Could the algae itself, still present in the first test, but not in the second, have an effect on the reading?

[chem geek]

I'm not sure how algae could make the CYA reading appear lower. That's a bit of a mystery unless perhaps the CYA tends to bind to the algea more than it binds to melamine (or vice versa where melamine binds to algae).

[CarlD]

Over MY paygrade! But we do know algae can break down CYA...is that POSSIBLY connected???

Of course, it's possible that what happened is how my teen describes the bulk of computer problems "The problem is between the keyboard and the chair!"

[okcnewbie]

I feel your pain about the coffee emergency. Next time you could make it like many RV boondockers. Heat water and pour through filter. (I'm sure you probably knew that already)