Where did my CY go?

[Jim Savage]

Just got my new VS pump up and running and uncovered the pool. Murky mess, but not unexpected.

So, I do a water test. CY is unreadable. Well, that's weird cause I was running around 30 when I shut it down, I pumped out just enough water to clear the returns so, I'm expecting 20 to 25 but not nothing! So I'm now into a SLAM and eating cal hypo like candy... fc is dropping to .5 by morning and I have to crank it back to 10 each morning. Checked the CC this morning and it was 4.5 so I'm definitely killing stuff, mostly tadpoles.

Anyway, any idea where my CY went? I didn't buy any as I chlorinated with tabs so I figured I'd be good enough to open and I'd monitor throughout the season. I did get 25 lbs of cal hypo... so at thus rate about 25% of what I probably needed at this rate.

Tips, pointers, advice, or ridicule welcome.

 

[mknauss]

This pool was just opened from being winterized?
If so, most likely ammonia.

Ammonia - Further Reading

www.troublefreepool.com

 

[magiteck]

A very small amount (maybe 5ppm/month) will naturally degrade over time.

Also, if you’re FC was at zero which based on the swamp sounds likely, there is a form of bacteria that can establish itself which “eats” cya and converts it into ammonia. That (in addition to the algae) would also increase the FC demand until the ammonia is cleared up.

 

[Jim Savage]

Well, that explains a lot. This is only my second season with this pool, and last season we had it relined. I feel like I'm going to learn a lot this year. First lesson, buy more SLAM friendly chlorine, as 25 lbs is just not enough. Lesson 2, the winter pill isn't going to last long enough, or at least not 7 months.

Thanks for the read, btw. Splains my dropping ph too. Ammonia certainly fits the scenario.

 

[magiteck]

Well, that explains a lot. This is only my second season with this pool, and last season we had it relined. I feel like I'm going to learn a lot this year. First lesson, buy more SLAM friendly chlorine, as 25 lbs is just not enough. Lesson 2, the winter pill isn't going to last long enough, or at least not 7 months.

For a “clean opening”, best bet is to open well before the water temperature reaches 60 degrees, and close after the water temperature falls below 60.

In the “shoulder seasons” while open chlorine usage is super low, so there’s not much added cost in being open longer.

For me, I closed in early October and opened in late April. Basically before/after there was a risk of prolonged sub-freezing temps.

For where you are now, though - SLAM Process away!

 

[MITBeta]

Lesson 2, the winter pill isn't going to last long enough, or at least not 7 months

I bought 3 exercise balls, each rated at 2000lbs and 3 ball nets (for carrying soccer or basket balls), inflated them inside the nets and tied the nets together with lines in the middle of the pool.

 

[Selenap]

I open sometime in March after the worst of the freezing is over. Pool temperature is usually in the low 50’s. Close in late October early November. Once I closed in September when the pool was still in the 80’s. I had to go on an extended trip. Opened to a swamp in March. I learned to close and open when the water stays in the 50’s.