How to test for CYA over 100?

[robrinker]

Long story short: I'm new to pools and have been "pool stored" since May.

I recently bought the Taylor K-2006 test kit and my CYA is testing well over 100.

Is there anything I can do to get a semi-accurate measurement of my CYA? I'm currently battling mustard algae and I'm trying to determine the exact amount of bleach I need to add to reach shock levels.

Thanks for all of the useful info posted here!

Ron

 

[Buggsw]

I would suppose that the shot glass method may help some.

Use distilled water and mix 1 shot of distilled water with 1 shot of pool sample water and then run the test.
Multiply the result by 2.

It won't be accurate but will give you a general idea, since you are way out of bounds to begin with.

For that matter, I think I would consider dumping more than half or all of your water and refilling. Considering of course your water situation and prices. Here, it only costs about $100 to refill 15K gallons.

 

[robrinker]

Does it have to be distilled water, or can I use tap water? I have well water. I tested it and it doesn't have any CYA in it.

The paint is peeling on my pool and I want to drain it in the spring and paint it, so I think I'm going to try to limp through this season (we only have about a month left here). Although, I may spend more in chemicals to do that than it would cost to drain and re-fill. I'm not sure what water costs around here, but I would imagine with Lake Erie about an hour north, it should be cheaper than in Arizona.

On that train of thought, can I drain my pool with the backwash feature of my filter, or would I risk damaging the filter?

Thanks!

 

[Buggsw]

I don't know about draining via backwash. I'm thinking it would suck air when it got below the skimmer. Whenever I've drained a pool I've used a sump pump and run the hose to the sewer. Perhaps, you could, though, via using your hose with a manual vac head to weigh it down.

I'm sure one of the experts with the mechanicals will be along to educate us, soon.

Believe it or not, water is cheap in Phoenix. Arizona sells water to California.

 

[robrinker]

I have a bottom drain, so I was thinking I could shut off my two skimmers and only have the drain pump water. Hooking up one of the skimmers to a hose and vac head sounds like a good idea as well. (what do you think, mech. experts?)

I would've never thought water would be cheap in the desert...any idea where your water comes from?

Used the shot glass method...my CYA is 170 (ouch)

 

[duraleigh]

I have a bottom drain, so I was thinking I could shut off my two skimmers and only have the drain pump water. Hooking up one of the skimmers to a hose and vac head sounds like a good idea as well. (what do you think, mech. experts?)

I would've never thought water would be cheap in the desert...any idea where your water comes from?

Used the shot glass method...my CYA is 170 (ouch)

Rob,

I don't see any reason why both of those approaches wouldn't work. You'll probably lose a lot of your sand, however. (unless your filter is DE)

A better approach (to me) would simply be to buy/borrow a submersible pump and pump it out. Even the little cheapies at HD/Lowes are fairly effective. you can look at their gpm capacity and get an idea of how long it will take to dump however much of your pool you dump. I suggest not draining much more than 50%....that'll get you a CYA of 80 which is high but manageable. If you're comfortable the pool is built well and not showing any cracks you perhaps could take a little more water than that but I'd get cautious over 50%.

 

[Buggsw]

We have a couple of huge canal systems.

One system ties into what's known as the Salt River Project where dams were built on the Salt and Verde rivers creating several lakes. Snowfall in the northern part of the state has a tremendous affect on these.

The other, newer system, is the Central Arizona Project which is a system of canals feeding from the Colorado River.

There's also a surprising amount of groundwater being pumped