Super High CYA / Algae

[Horns99]

just took over my own pool duties. Pool has for years been taken care by a pool company that used pucks & shock. Tested everything tonight w/ the TF100 Kit.
Its obvious I have a algae problem along with tons of pollen falling in the pool down here in Houston currently.
My test # are FC: 6; TC: 7.5; CH: 400; TA: 90; PH: 7.5ish; CYA: 100. From my research I need to drain & refill, my question is how much water do I need to drain?
My pool is approx 25K gallons & water is expensive.... Pool definitely currently has a green tint to it & is very cloudy.
Any help / suggestions is appreciated.

 

[mknauss]

Welcome to the forum.

Run the extended CYA test. See CYA Testing - Further Reading

 

[StephenRMcKay]

I had the same issues last summer. Wasted thousands of dollars on shock and chemicals. After the mods here enlightened me on CYA levels, and proper water exchange methods, it completely changed the whole game. I did a 70% water exchange (took about 3 or 4 days and cost about $175 in water) but it was so worth it. Let me know if you need any help with the exchange. I'd be glad to walk you through the steps I took to do mine.

 

[Rancho Cost-a-Lotta]

Please fill out your location. This is important when providing guidance related to water chemistry.

 

[Horns99]

Says Houston in the post. Texas

 

[proavia]

Says Houston in the post. Texas

Great - add it to your profile so we all know for next time.

Welcome to TFP!

Also please fill out your signature with your pool, pool equipment (including manufacturers and model numbers) and test kit info. This will make it easier for us to provide guidance in the future.